Load pcre-1.00 into code/trunk.

git-svn-id: svn://vcs.exim.org/pcre/code/trunk@3 2f5784b3-3f2a-0410-8824-cb99058d5e15

22 files changed, 12534 insertions, 0 deletions

diff --git a/ChangeLog b/ChangeLog
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index 0000000..0227726
--- /dev/null
+++ b/ChangeLog
@@ -0,0 +1,173 @@
+ChangeLog for PCRE
+------------------
+
+Version 0.99 27-Oct-97
+----------------------
+
+1. Fixed bug in code for optimizing classes with only one character. It was
+initializing a 32-byte map regardless, which could cause it to run off the end
+of the memory it had got.
+
+2. Added, conditional on PCRE_EXTRA, the proposed (?>REGEX) construction.
+
+
+Version 0.98 22-Oct-97
+----------------------
+
+1. Fixed bug in code for handling temporary memory usage when there are more
+back references than supplied space in the ovector. This could cause segfaults.
+
+
+Version 0.97 21-Oct-97
+----------------------
+
+1. Added the \X "cut" facility, conditional on PCRE_EXTRA.
+
+2. Optimized negated single characters not to use a bit map.
+
+3. Brought error texts together as macro definitions; clarified some of them;
+fixed one that was wrong - it said "range out of order" when it meant "invalid
+escape sequence".
+
+4. Changed some char * arguments to const char *.
+
+5. Added PCRE_NOTBOL and PCRE_NOTEOL (from POSIX).
+
+6. Added the POSIX-style API wrapper in pcreposix.a and testing facilities in
+pcretest.
+
+
+Version 0.96 16-Oct-97
+----------------------
+
+1. Added a simple "pgrep" utility to the distribution.
+
+2. Fixed an incompatibility with Perl: "{" is now treated as a normal character
+unless it appears in one of the precise forms "{ddd}", "{ddd,}", or "{ddd,ddd}"
+where "ddd" means "one or more decimal digits".
+
+3. Fixed serious bug. If a pattern had a back reference, but the call to
+pcre_exec() didn't supply a large enough ovector to record the related
+identifying subpattern, the match always failed. PCRE now remembers the number
+of the largest back reference, and gets some temporary memory in which to save
+the offsets during matching if necessary, in order to ensure that
+backreferences always work.
+
+4. Increased the compatibility with Perl in a number of ways:
+
+  (a) . no longer matches \n by default; an option PCRE_DOTALL is provided
+      to request this handling. The option can be set at compile or exec time.
+
+  (b) $ matches before a terminating newline by default; an option
+      PCRE_DOLLAR_ENDONLY is provided to override this (but not in multiline
+      mode). The option can be set at compile or exec time.
+
+  (c) The handling of \ followed by a digit other than 0 is now supposed to be
+      the same as Perl's. If the decimal number it represents is less than 10
+      or there aren't that many previous left capturing parentheses, an octal
+      escape is read. Inside a character class, it's always an octal escape,
+      even if it is a single digit.
+
+  (d) An escaped but undefined alphabetic character is taken as a literal,
+      unless PCRE_EXTRA is set. Currently this just reserves the remaining
+      escapes.
+
+  (e) {0} is now permitted. (The previous item is removed from the compiled
+      pattern).
+
+5. Changed all the names of code files so that the basic parts are no longer
+than 10 characters, and abolished the teeny "globals.c" file.
+
+6. Changed the handling of character classes; they are now done with a 32-byte
+bit map always.
+
+7. Added the -d and /D options to pcretest to make it possible to look at the
+internals of compilation without having to recompile pcre.
+
+
+Version 0.95 23-Sep-97
+----------------------
+
+1. Fixed bug in pre-pass concerning escaped "normal" characters such as \x5c or
+\x20 at the start of a run of normal characters. These were being treated as
+real characters, instead of the source characters being re-checked.
+
+
+Version 0.94 18-Sep-97
+----------------------
+
+1. The functions are now thread-safe, with the caveat that the global variables
+containing pointers to malloc() and free() or alternative functions are the
+same for all threads.
+
+2. Get pcre_study() to generate a bitmap of initial characters for non-
+anchored patterns when this is possible, and use it if passed to pcre_exec().
+
+
+Version 0.93 15-Sep-97
+----------------------
+
+1. /(b)|(:+)/ was computing an incorrect first character.
+
+2. Add pcre_study() to the API and the passing of pcre_extra to pcre_exec(),
+but not actually doing anything yet.
+
+3. Treat "-" characters in classes that cannot be part of ranges as literals,
+as Perl does (e.g. [-az] or [az-]).
+
+4. Set the anchored flag if a branch starts with .* or .*? because that tests
+all possible positions.
+
+5. Split up into different modules to avoid including unneeded functions in a
+compiled binary. However, compile and exec are still in one module. The "study"
+function is split off.
+
+6. The character tables are now in a separate module whose source is generated
+by an auxiliary program - but can then be edited by hand if required. There are
+now no calls to isalnum(), isspace(), isdigit(), isxdigit(), tolower() or
+toupper() in the code.
+
+7. Turn the malloc/free funtions variables into pcre_malloc and pcre_free and
+make them global. Abolish the function for setting them, as the caller can now
+set them directly.
+
+
+Version 0.92 11-Sep-97
+----------------------
+
+1. A repeat with a fixed maximum and a minimum of 1 for an ordinary character
+(e.g. /a{1,3}/) was broken (I mis-optimized it).
+
+2. Caseless matching was not working in character classes if the characters in
+the pattern were in upper case.
+
+3. Make ranges like [W-c] work in the same way as Perl for caseless matching.
+
+4. Make PCRE_ANCHORED public and accept as a compile option.
+
+5. Add an options word to pcre_exec() and accept PCRE_ANCHORED and
+PCRE_CASELESS at run time. Add escapes \A and \I to pcretest to cause it to
+pass them.
+
+6. Give an error if bad option bits passed at compile or run time.
+
+7. Add PCRE_MULTILINE at compile and exec time, and (?m) as well. Add \M to
+pcretest to cause it to pass that flag.
+
+8. Add pcre_info(), to get the number of identifying subpatterns, the stored
+options, and the first character, if set.
+
+9. Recognize C+ or C{n,m} where n >= 1 as providing a fixed starting character.
+
+
+Version 0.91 10-Sep-97
+----------------------
+
+1. PCRE was failing to diagnose unlimited repeats of subpatterns that could
+match the empty string as in /(a*)*/. It was looping and ultimately crashing.
+
+2. PCRE was looping on encountering an indefinitely repeated back reference to
+a subpattern that had matched an empty string, e.g. /(a|)\1*/. It now does what
+Perl does - treats the match as successful.
+
+****
diff --git a/Makefile b/Makefile
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+++ b/Makefile
@@ -0,0 +1,73 @@
+# Make file for PCRE (Perl-Compatible Regular Expression) library.
+
+# Edit CC , CFLAGS, and RANLIB for your system.
+
+# It is believed that RANLIB=ranlib is required for AIX, BSDI, FreeBSD, Linux,
+# MIPS RISCOS, NetBSD, OpenBSD, Digital Unix, and Ultrix.
+
+# Use CFLAGS = -DUSE_BCOPY on SunOS4 and any other system that lacks the
+# memmove() function, but has bcopy().
+
+# Use CFLAGS = -DSTRERROR_FROM_ERRLIST on SunOS4 and any other system that
+# lacks the strerror() function, but can provide the equivalent by indexing
+# into errlist.
+
+CC = gcc -O
+CFLAGS =
+RANLIB = @true
+
+##########################################################################
+
+OBJ = chartables.o study.o pcre.o
+
+all:            libpcre.a libpcreposix.a pcretest pgrep
+
+pgrep:          libpcre.a pgrep.o
+		$(CC) $(CFLAGS) -o pgrep pgrep.o libpcre.a
+
+pcretest:       libpcre.a libpcreposix.a pcretest.o
+		$(CC) $(CFLAGS) -o pcretest pcretest.o libpcre.a libpcreposix.a
+
+libpcre.a:      $(OBJ)
+		/bin/rm -f libpcre.a
+		ar cq libpcre.a $(OBJ)
+		$(RANLIB) libpcre.a
+
+libpcreposix.a: pcreposix.o
+		/bin/rm -f libpcreposix.a
+		ar cq libpcreposix.a pcreposix.o
+		$(RANLIB) libpcreposix.a
+
+pcre.o:         pcre.c pcre.h internal.h
+		$(CC) -c $(CFLAGS) pcre.c
+
+pcreposix.o:    pcreposix.c pcreposix.h internal.h
+		$(CC) -c $(CFLAGS) pcreposix.c
+
+chartables.o:   chartables.c
+		$(CC) -c $(CFLAGS) chartables.c
+
+study.o:        study.c pcre.h internal.h
+		$(CC) -c $(CFLAGS) study.c
+
+pcretest.o:     pcretest.c pcre.h
+		$(CC) -c $(CFLAGS) pcretest.c
+
+pgrep.o:        pgrep.c pcre.h
+		$(CC) -c $(CFLAGS) pgrep.c
+
+# An auxiliary program makes the character tables
+
+chartables.c:    maketables
+		./maketables >chartables.c
+
+maketables:     maketables.c
+		$(CC) -o maketables $(CFLAGS) maketables.c
+
+# We deliberately omit maketables and chartables.c from 'make clean'; once made
+# chartables.c shouldn't change, and if people have edited the tables by hand,
+# you don't want to throw them away.
+
+clean:;         /bin/rm -f *.o *.a pcretest pgrep
+
+# End
diff --git a/Performance b/Performance
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+++ b/Performance
@@ -0,0 +1,172 @@
+Some comparisons of PCRE with the original Henry Spencer (1986) regular
+expression functions were done on a SPARCstation IPC using gcc version 2.6.3
+with -O optimization, to give some idea as to how the two libraries compare.
+This is not a major statistical investigation.
+
+
+Code size
+---------
+
+The code size of PCRE is a bit over twice the size of the Henry Spencer
+functions (roughly 33K vs 14K bytes on a SPARCstation with gcc -O).
+
+
+Store size for compiled expressions
+-----------------------------------
+
+For expressions that are compatible with both libraries, PCRE uses less store
+for the examples tried, except in some cases that involve the use of character
+classes. Except in the special case of a negated charcter class containing only
+one character (e.g. [^a]), PCRE uses a 32-byte bit map for each character
+class, in order to get the maximum matching speed. By contrast the Spencer code
+uses a strchr() call.
+
+The Spencer functions have an overhead of 92 bytes per expression, because
+there is a table for up to 10 matched substrings held with every compiled
+expression. In contrast, PCRE's overhead is just 9 bytes, since it requires the
+caller to supply a vector to receive the offsets of the matched substrings. In
+the table below, the size without the overhead is shown in brackets.
+
+PCRE      Spencer       Pattern
+----      -------       -------
+
+ 18 (09)    109 (17)    /^$/
+ 25 (16)    120 (28)    /^.*nter/
+ 26 (17)    121 (29)    /^12.34/
+ 37 (28)    126 (34)    /the quick brown fox/
+ 50 (41)    114 (22)    /^[]cde]/
+ 50 (41)    114 (22)    /^[^]cde]/
+ 51 (42)    125 (33)    /^[.^$|()*+?{,}]+/
+ 52 (43)    126 (34)    /^[0-9]+$/
+ 56 (47)    153 (61)    /^(abc)(abc)?zz/
+ 57 (48)    133 (41)    /^xxx[0-9]+$/
+ 57 (48)    145 (53)    /([0-9a-fA-F:]+)$/
+ 62 (53)    171 (79)    /^([^!]+)!(.+)=apquxz\.ixr\.zzz\.ac\.uk$$/
+ 70 (61)    170 (78)    /^(b+|a)(b+|a)?c/
+ 74 (65)    173 (81)    /^(ba|b*)(ba|b*)?bc/
+ 99 (90)    235 (143)   /^(a(b(c)))(d(e(f)))(h(i(j)))$/
+119 (110)   157 (65)    /^.+[0-9][0-9][0-9]$/
+165 (156)   446 (354)   /^[a-zA-Z0-9][a-zA-Z0-9\-]*(\.[a-zA-Z0-9][a-zA-z0-9\-]*)*\.$/
+451 (442)   605 (513)   /^From +([^ ]+) +[a-zA-Z][a-zA-Z][a-zA-Z] +[a-zA-Z][a-zA-Z][a-zA-Z] +[0-9]?[0-9] +[0-9][0-9]:[0-9][0-9]/
+
+
+Compilation time
+----------------
+
+Timing was done using the clock() function to time 2000 compilations of each
+expression and then dividing by twice the number of clocks per second, to get a
+value in milliseconds. The variation observed over several runs was never more
+than 0.01:
+
+PCRE      Spencer       Pattern
+----      -------       -------
+
+0.04       0.07         /^$/
+0.06       0.12         /^.*nter/
+0.06       0.13         /^12.34/
+0.06       0.09         /^[]cde]/
+0.07       0.14         /^[0-9]+$/
+0.07       0.10         /^[^]cde]/
+0.08       0.17         /^xxx[0-9]+$/
+0.08       0.14         /the quick brown fox/
+0.09       0.14         /^[.^$|()*+?{,}]+/
+0.10       0.33         /([0-9a-fA-F:]+)$/
+0.12       0.26         /^.+[0-9][0-9][0-9]$/
+0.12       0.42         /^(abc)(abc)?zz/
+0.14       0.51         /^(b+|a)(b+|a)?c/
+0.15       0.53         /^(ba|b*)(ba|b*)?bc/
+0.19       0.51         /^([^!]+)!(.+)=apquxz\.ixr\.zzz\.ac\.uk$/
+0.34       1.59         /^(a(b(c)))(d(e(f)))(h(i(j)))$/
+0.47       1.32         /^[a-zA-Z0-9][a-zA-Z0-9\-]*(\.[a-zA-Z0-9][a-zA-z0-9\-]*)*\.$/
+0.66       1.78         /^From +([^ ]+) +[a-zA-Z][a-zA-Z][a-zA-Z] +[a-zA-Z][a-zA-Z][a-zA-Z] +[0-9]?[0-9] +[0-9][0-9]:[0-9][0-9]/
+
+
+Execution time
+--------------
+
+Execution timing was done in a similar manner. Blank entries in the "pattern"
+column below indicate the use of the same pattern as before.
+
+PCRE   Spencer   Subject                Pattern
+----   -------   -------                -------
+
+0.03     0.02    <null string>          /^$/
+0.04     0.04    enter                  /^.*nter/
+0.04     0.04    uponter
+0.03     0.03    12\r34                 /^12.34/
+0.03     0.03    0                      /^[0-9]+$/
+0.04     0.03    100
+0.03     0.03    ]thing                 /^[]cde]/
+0.03     0.03    ething
+0.03     0.03    athing                 /^[^]cde]/
+0.04     0.04    xxx0                   /^xxx[0-9]+$/
+0.04     0.04    xxx1234
+0.04     0.07    .^\$(*+)|{?,?}         /^[.^$|()*+?{,}]+/
+0.03     0.03    the quick brown fox    /the quick brown fox/
+0.06     0.08    What do you know about the quick brown fox?
+0.04     0.07    0abc                   /([0-9a-fA-F:]+)$/
+0.04     0.07    abc
+0.05     0.13    5f03:12C0::932e
+0.06     0.07    x123                   /^.+[0-9][0-9][0-9]$/
+0.06     0.07    123456
+0.06     0.09    abczz                  /^(abc)(abc)?zz/
+0.06     0.12    abcabczz               /^(abc)(abc)?zz/
+                                        /^([^!]+)!(.+)=apquxz\.ixr\.zzz\.ac\.uk$/
+0.23     0.28    abc!pqr=apquxz.ixr.zzz.ac.uk
+0.09     0.15    bc                     /^(b+|a)(b+|a)?c/
+0.09     0.15    bbc
+0.08     0.15    bbbc
+0.09     0.15    bac
+0.09     0.15    bbac
+0.07     0.14    aac
+0.09     0.15    abbbbbbbbbbbc
+0.09     0.15    bbbbbbbbbbbac
+0.09     0.18    babc                   /^(ba|b*)(ba|b*)?bc/
+0.12     0.24    bbabc
+0.07     0.15    bababc
+0.06     0.10    a.                     /^[a-zA-Z0-9][a-zA-Z0-9\-]*(\.[a-zA-Z0-9][a-zA-z0-9\-]*)*\.$/
+0.13     0.34    ab-c.pq-r.
+0.24     0.58    sxk.zzz.ac.uk.
+0.12     0.34    x-.y-.
+0.20     0.38    abcdefhij              /^(a(b(c)))(d(e(f)))(h(i(j)))$/
+                                        /^From +([^ ]+) +[a-zA-Z][a-zA-Z][a-zA-Z] +[a-zA-Z][a-zA-Z][a-zA-Z] +[0-9]?[0-9] +[0-9][0-9]:[0-9][0-9]/
+0.18     0.30    From abcd  Mon Sep 01 12:33:02 1997
+
+In general, PCRE runs faster than the Spencer function, but remember, this
+is just for one particular compiler on one set of hardware and operating
+system. Until comprehensive tests have been run in other environments, the most
+one can plausibly say is that it is probably no worse on average for the kinds
+of expression tested here.
+
+
+Speeding up matching
+--------------------
+
+A character class is much more efficient than a set of bracketed alternatives.
+Matching /^[abc]{12}/ against "abcabcabcabc" took 0.03 ms, whereas
+/^(a|b|c){12}/ took 0.33 ms. This is because brackets and alternatives involve
+recursion.
+
+
+Serious test
+------------
+
+One of the tests of PCRE is the monster regular expression from "Mastering
+Regular Expressions" (O'Reilly's "hip owls" book, 1997, ISBN 1-56592-257-3)
+which recognizes email addresses. There are two versions, unoptimized and
+optimized. For interest, here are their timings, again on a SPARCstation IPC.
+The compile times were 55 ms and 94 ms, and the compiled expressions
+occupied 11010 and 15426 bytes of store, respectively. The following strings
+were matched in the times shown (unoptimized first):
+
+0.34  0.38   user@dom.ain
+0.38  0.42   <user@dom.ain>
+0.88  0.60   Alan Other <user@dom.ain>
+1.87  0.82   "A. Other" <user.1234@dom.ain> (a comment)
+1.77  1.19   A. Other <user.1234@dom.ain> (a comment)
+2.21  0.42   "/s=user/ou=host/o=place/prmd=uu.yy/admd= /c=gb/"@x400-re.lay
+
+The optimization of the expression clearly has a dramatic effect in some cases.
+
+Philip Hazel <ph10@cus.cam.ac.uk>
+October 1997
diff --git a/README b/README
new file mode 100644
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--- /dev/null
+++ b/README
@@ -0,0 +1,233 @@
+README file for PCRE (Perl-compatible regular expressions)
+----------------------------------------------------------
+
+The distribution should contain the following files:
+
+  ChangeLog         log of changes to the code
+  Makefile          for building PCRE
+  Performance       notes on performance
+  README            this file
+  Tech.Notes        notes on the encoding
+  pcre.3            man page for the functions
+  pcreposix.3       man page for the POSIX wrapper API
+  maketables.c      auxiliary program for building chartables.c
+  study.c           ) source of
+  pcre.c            )   the functions
+  pcreposix.c       )
+  pcre.h            header for the external API
+  pcreposix.h       header for the external POSIX wrapper API
+  internal.h        header for internal use
+  pcretest.c        test program
+  pgrep.1           man page for pgrep
+  pgrep.c           source of a grep utility that uses PCRE
+  perltest          Perl test program
+  testinput         test data, compatible with Perl
+  testinput2        test data for error messages and non-Perl things
+  testoutput        test results corresponding to testinput
+  testoutput2       test results corresponding to testinput2
+
+To build PCRE, edit Makefile for your system (it is a fairly simple make file)
+and then run it. It builds a two libraries called libpcre.a and libpcreposix.a,
+a test program called pcretest, and the pgrep command.
+
+To test PCRE, run pcretest on the file testinput, and compare the output with
+the contents of testoutput. There should be no differences. For example:
+
+  pcretest testinput /tmp/anything
+  diff /tmp/anything testoutput
+
+Do the same with testinput2, comparing the output with testoutput2, but this
+time using the -i flag for pcretest, i.e.
+
+  pcretest -i testinput2 /tmp/anything
+  diff /tmp/anything testoutput2
+
+There are two sets of tests because the first set can also be fed directly into
+the perltest program to check that Perl gives the same results. The second set
+of tests check pcre_info(), pcre_study(), error detection and run-time flags
+that are specific to PCRE, as well as the POSIX wrapper API.
+
+To install PCRE, copy libpcre.a to any suitable library directory (e.g.
+/usr/local/lib), pcre.h to any suitable include directory (e.g.
+/usr/local/include), and pcre.3 to any suitable man directory (e.g.
+/usr/local/man/man3).
+
+To install the pgrep command, copy it to any suitable binary directory, (e.g.
+/usr/local/bin) and pgrep.1 to any suitable man directory (e.g.
+/usr/local/man/man1).
+
+PCRE has its own native API, but a set of "wrapper" functions that are based on
+the POSIX API are also supplied in the library libpcreposix.a. Note that this
+just provides a POSIX calling interface to PCRE: the regular expressions
+themselves still follow Perl syntax and semantics. The header file
+for the POSIX-style functions is called pcreposix.h. The official POSIX name is
+regex.h, but I didn't want to risk possible problems with existing files of
+that name by distributing it that way. To use it with an existing program that
+uses the POSIX API it will have to be renamed or pointed at by a link.
+
+
+Character tables
+----------------
+
+PCRE uses four tables for manipulating and identifying characters. These are
+compiled from a source file called chartables.c. This is not supplied in
+the distribution, but is built by the program maketables (compiled from
+maketables.c), which uses the ANSI C character handling functions such as
+isalnum(), isalpha(), isupper(), islower(), etc. to build the table sources.
+This means that the default C locale set in your system may affect the contents
+of the tables. You can change the tables by editing chartables.c and then
+re-building PCRE. If you do this, you should probably also edit Makefile to
+ensure that the file doesn't ever get re-generated.
+
+The first two tables pcre_lcc[] and pcre_fcc[] provide lower casing and a
+case flipping functions, respectively. The pcre_cbits[] table consists of four
+32-byte bit maps which identify digits, letters, "word" characters, and white
+space, respectively. These are used when building 32-byte bit maps that
+represent character classes.
+
+The pcre_ctypes[] table has bits indicating various character types, as
+follows:
+
+    1   white space character
+    2   letter
+    4   decimal digit
+    8   hexadecimal digit
+   16   alphanumeric or '_'
+  128   regular expression metacharacter or binary zero
+
+You should not alter the set of characters that contain the 128 bit, as that
+will cause PCRE to malfunction.
+
+
+The pcretest program
+--------------------
+
+This program is intended for testing PCRE, but it can also be used for
+experimenting with regular expressions.
+
+If it is given two filename arguments, it reads from the first and writes to
+the second. If it is given only one filename argument, it reads from that file
+and writes to stdout. Otherwise, it reads from stdin and writes to stdout, and
+prompts for each line of input.
+
+The program handles any number of sets of input on a single input file. Each
+set starts with a regular expression, and continues with any number of data
+lines to be matched against the pattern. An empty line signals the end of the
+set. The regular expressions are given enclosed in any non-alphameric
+delimiters, for example
+
+  /(a|bc)x+yz/
+
+and may be followed by i, m, s, or x to set the PCRE_CASELESS, PCRE_MULTILINE,
+PCRE_DOTALL, or PCRE_EXTENDED options, respectively. These options have the
+same effect as they do in Perl.
+
+There are also some upper case options that do not match Perl options: /A, /E,
+and /X set PCRE_ANCHORED, PCRE_DOLLAR_ENDONLY, and PCRE_EXTRA respectively.
+The /D option is a PCRE debugging feature. It causes the internal form of
+compiled regular expressions to be output after compilation. The /S option
+causes pcre_study() to be called after the expression has been compiled, and
+the results used when the expression is matched. If /I is present as well as
+/S, then pcre_study() is called with the PCRE_CASELESS option.
+
+Finally, the /P option causes pcretest to call PCRE via the POSIX wrapper API
+rather than its native API. When this is done, all other options except /i and
+/m are ignored. REG_ICASE is set if /i is present, and REG_NEWLINE is set if /m
+is present. The wrapper functions force PCRE_DOLLAR_ENDONLY always, and
+PCRE_DOTALL unless REG_NEWLINE is set.
+
+A regular expression can extend over several lines of input; the newlines are
+included in it. See the testinput file for many examples.
+
+Before each data line is passed to pcre_exec(), leading and trailing whitespace
+is removed, and it is then scanned for \ escapes. The following are recognized:
+
+  \a     alarm (= BEL)
+  \b     backspace
+  \e     escape
+  \f     formfeed
+  \n     newline
+  \r     carriage return
+  \t     tab
+  \v     vertical tab
+  \nnn   octal character (up to 3 octal digits)
+  \xhh   hexadecimal character (up to 2 hex digits)
+
+  \A     pass the PCRE_ANCHORED option to pcre_exec()
+  \B     pass the PCRE_NOTBOL option to pcre_exec()
+  \E     pass the PCRE_DOLLAR_ENDONLY option to pcre_exec()
+  \I     pass the PCRE_CASELESS option to pcre_exec()
+  \M     pass the PCRE_MULTILINE option to pcre_exec()
+  \S     pass the PCRE_DOTALL option to pcre_exec()
+  \Odd   set the size of the output vector passed to pcre_exec() to dd
+           (any number of decimal digits)
+  \Z     pass the PCRE_NOTEOL option to pcre_exec()
+
+A backslash followed by anything else just escapes the anything else. If the
+very last character is a backslash, it is ignored. This gives a way of passing
+an empty line as data, since a real empty line terminates the data input.
+
+If /P was present on the regex, causing the POSIX wrapper API to be used, only
+\B, and \Z have any effect, causing REG_NOTBOL and REG_NOTEOL to be passed to
+regexec() respectively.
+
+When a match succeeds, pcretest outputs the list of identified substrings that
+pcre_exec() returns, starting with number 0 for the string that matched the
+whole pattern. Here is an example of an interactive pcretest run.
+
+  $ pcretest
+  Testing Perl-Compatible Regular Expressions
+  PCRE version 0.90 08-Sep-1997
+
+      re> /^abc(\d+)/
+    data> abc123
+   0: abc123
+   1: 123
+    data> xyz
+  No match
+
+Note that while patterns can be continued over several lines (a plain ">"
+prompt is used for continuations), data lines may not. However newlines can be
+included in data by means of the \n escape.
+
+If the -p option is given to pcretest, it is equivalent to adding /P to each
+regular expression: the POSIX wrapper API is used to call PCRE. None of the
+following flags has any effect in this case.
+
+If the option -d is given to pcretest, it is equivalent to adding /D to each
+regular expression: the internal form is output after compilation.
+
+If the option -i (for "information") is given to pcretest, it calls pcre_info()
+after compiling an expression, and outputs the information it gets back. If the
+pattern is studied, the results of that are also output.
+
+If the option -s is given to pcretest, it outputs the size of each compiled
+pattern after it has been compiled.
+
+If the -t option is given, each compile, study, and match is run 2000 times
+while being timed, and the resulting time per compile or match is output in
+milliseconds. Do not set -t with -s, because you will then get the size output
+2000 times and the timing will be distorted.
+
+
+
+The perltest program
+--------------------
+
+The perltest program tests Perl's regular expressions; it has the same
+specification as pcretest, and so can be given identical input, except that
+input patterns can be followed only by Perl's lower case options.
+
+The data lines are processed as Perl strings, so if they contain $ or @
+characters, these have to be escaped. For this reason, all such characters in
+the testinput file are escaped so that it can be used for perltest as well as
+for pcretest, and the special upper case options such as /A that pcretest
+recognizes are not used in this file. The output should be identical, apart
+from the initial identifying banner.
+
+The testinput2 file is not suitable for feeding to Perltest, since it does
+make use of the special upper case options and escapes that pcretest uses to
+test additional features of PCRE.
+
+Philip Hazel <ph10@cam.ac.uk>
+October 1997
diff --git a/Tech.Notes b/Tech.Notes
new file mode 100644
index 0000000..f17b661
--- /dev/null
+++ b/Tech.Notes
@@ -0,0 +1,199 @@
+Technical Notes about PCRE
+--------------------------
+
+Many years ago I implemented some regular expression functions to an algorithm
+suggested by Martin Richards. These were not Unix-like in form, and were quite
+restricted in what they could do by comparison with Perl. The interesting part
+about the algorithm was that the amount of space required to hold the compiled
+form of an expression was known in advance. The code to apply an expression did
+not operate by backtracking, as the Henry Spencer and Perl code does, but
+instead checked all possibilities simultaneously by keeping a list of current
+states and checking all of them as it advanced through the subject string. (In
+the terminology of Jeffrey Friedl's book, it was a "DFA algorithm".) When the
+pattern was all used up, all remaining states were possible matches, and the
+one matching the longest subset of the subject string was chosen. This did not
+necessarily maximize the individual wild portions of the pattern, as is
+expected in Unix and Perl-style regular expressions.
+
+By contrast, the code originally written by Henry Spencer and subsequently
+heavily modified for Perl actually compiles the expression twice: once in a
+dummy mode in order to find out how much store will be needed, and then for
+real. The execution function operates by backtracking and maximizing (or
+minimizing in Perl) the amount of the subject that matches individual wild
+portions of the pattern. This is a "NFA algorithm".
+
+For this set of functions, I tried at first to invent an algorithm that used an
+amount of store bounded by a multiple of the number of characters in the
+pattern, to save on compiling time. However, because of the greater complexity
+in Perl regular expressions, I couldn't do this. In any case, a first pass
+through the pattern is needed, in order to find internal flag settings like
+(?i). So it works by running a very degenerate first pass to calculate a
+maximum store size, and then a second pass to do the real compile - which may
+use a bit less than the predicted amount of store. The idea is that this is
+going to turn out faster because the first pass is degenerate and the second
+can just store stuff straight into the vector. It does make the compiling
+functions bigger, of course, but they have got quite big anyway to handle all
+the Perl stuff.
+
+The compiled form of a pattern is a vector of bytes, containing items of
+variable length. The first byte in an item is an opcode, and the length of the
+item is either implicit in the opcode or contained in the data bytes which
+follow it. A list of all the opcodes follows:
+
+Opcodes with no following data
+------------------------------
+
+These items are all just one byte long
+
+  OP_END                 end of pattern
+  OP_ANY                 match any character
+  OP_SOD                 match start of data: \A
+  OP_CIRC                ^ (start of data, or after \n in multiline)
+  OP_NOT_WORD_BOUNDARY   \W
+  OP_WORD_BOUNDARY       \w
+  OP_NOT_DIGIT           \D
+  OP_DIGIT               \d
+  OP_NOT_WHITESPACE      \S
+  OP_WHITESPACE          \s
+  OP_NOT_WORDCHAR        \W
+  OP_WORDCHAR            \w
+  OP_CUT                 analogue of Prolog's "cut"
+  OP_EOD                 match end of data: \Z
+  OP_DOLL                $ (end of data, or before \n in multiline)
+
+
+Repeating single characters
+---------------------------
+
+The common repeats (*, +, ?) when applied to a single character appear as
+two-byte items using the following opcodes:
+
+  OP_STAR
+  OP_MINSTAR
+  OP_PLUS
+  OP_MINPLUS
+  OP_QUERY
+  OP_MINQUERY
+
+Those with "MIN" in their name are the minimizing versions. Each is followed by
+the character that is to be repeated. Other repeats make use of
+
+  OP_UPTO
+  OP_MINUPTO
+  OP_EXACT
+
+which are followed by a two-byte count (most significant first) and the
+repeated character. OP_UPTO matches from 0 to the given number. A repeat with a
+non-zero minimum and a fixed maximum is coded as an OP_EXACT followed by an
+OP_UPTO (or OP_MINUPTO).
+
+
+Repeating character types
+-------------------------
+
+Repeats of things like \d are done exactly as for single characters, except
+that instead of a character, the opcode for the type is stored in the data
+byte. The opcodes are:
+
+  OP_TYPESTAR
+  OP_TYPEMINSTAR
+  OP_TYPEPLUS
+  OP_TYPEMINPLUS
+  OP_TYPEQUERY
+  OP_TYPEMINQUERY
+  OP_TYPEUPTO
+  OP_TYPEMINUPTO
+  OP_TYPEEXACT
+
+
+Matching a character string
+---------------------------
+
+The OP_CHARS opcode is followed by a one-byte count and then that number of
+characters. If there are more than 255 characters in sequence, successive
+instances of OP_CHARS are used.
+
+
+Character classes
+-----------------
+
+OP_CLASS is used for a character class. It is followed by a 32-byte bit map
+containing a 1 bit for every character that is acceptable. The bits are counted
+from the least significant end of each byte.
+
+
+Back references
+---------------
+
+OP_REF is followed by a single byte containing the reference number.
+
+
+Repeating character classes and back references
+-----------------------------------------------
+
+In both cases, the repeat information follows the base item. The matching code
+looks at the following opcode to see if it is one of
+
+  OP_CRSTAR
+  OP_CRMINSTAR
+  OP_CRPLUS
+  OP_CRMINPLUS
+  OP_CRQUERY
+  OP_CRMINQUERY
+  OP_CRRANGE
+  OP_CRMINRANGE
+
+All but the last two are just single-byte items. The others are followed by
+four bytes of data, comprising the minimum and maximum repeat counts.
+
+
+Brackets and alternation
+------------------------
+
+A pair of non-identifying (round) brackets is wrapped round each expression at
+compile time, so alternation always happens in the context of brackets.
+Non-identifying brackets use the opcode OP_BRA, while identifying brackets use
+OP_BRA+1, OP_BRA+2, etc. [Note for North Americans: "bracket" to some English
+speakers, including myself, can be round, square, or curly. Hence this usage.]
+
+A bracket opcode is followed by two bytes which give the offset to the next
+alternative OP_ALT or, if there aren't any branches, to the matching KET
+opcode. Each OP_ALT is followed by two bytes giving the offset to the next one,
+or to the KET opcode.
+
+OP_KET is used for subpatterns that do not repeat indefinitely, while
+OP_KETRMIN and OP_KETRMAX are used for indefinite repetitions, minimally or
+maximally respectively. All three are followed by two bytes giving (as a
+positive number) the offset back to the matching BRA opcode.
+
+If a subpattern is quantified such that it is permitted to match zero times, it
+is preceded by one of OP_BRAZERO or OP_BRAMINZERO. These are single-byte
+opcodes which tell the matcher that skipping this subpattern entirely is a
+valid branch.
+
+A subpattern with an indefinite maximum repetition is replicated in the
+compiled data its minimum number of times (or once with a BRAZERO if the
+minimum is zero), with the final copy terminating with a KETRMIN or KETRMAX as
+appropriate.
+
+A subpattern with a bounded maximum repetition is replicated up to the maximum
+number of times, with BRAZERO or BRAMINZERO before each replication after the
+minimum. In effect, (abc){2,5} becomes (abc)(abc)(abc)?(abc)?(abc)?.
+
+
+Assertions
+----------
+
+Assertions are just like other subpatterns, but starting with one of the
+opcodes OP_ASSERT or OP_ASSERT_NOT.
+
+
+Once-only subpatterns
+---------------------
+
+These are also just like other subpatterns, but they start with the opcode
+OP_ONCE.
+
+
+Philip Hazel
+October 1997
diff --git a/internal.h b/internal.h
new file mode 100644
index 0000000..1ba868d
--- /dev/null
+++ b/internal.h
@@ -0,0 +1,281 @@
+/*************************************************
+*      Perl-Compatible Regular Expressions       *
+*************************************************/
+
+
+#define PCRE_VERSION       "1.00 18-Nov-1997"
+
+
+/* This is a library of functions to support regular expressions whose syntax
+and semantics are as close as possible to those of the Perl 5 language. See
+the file Tech.Notes for some information on the internals.
+
+Written by: Philip Hazel <ph10@cam.ac.uk>
+
+           Copyright (c) 1997 University of Cambridge
+
+-----------------------------------------------------------------------------
+Permission is granted to anyone to use this software for any purpose on any
+computer system, and to redistribute it freely, subject to the following
+restrictions:
+
+1. This software is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+
+2. The origin of this software must not be misrepresented, either by
+   explicit claim or by omission.
+
+3. Altered versions must be plainly marked as such, and must not be
+   misrepresented as being the original software.
+-----------------------------------------------------------------------------
+*/
+
+/* This header contains definitions that are shared between the different
+modules, but which are not relevant to the outside. */
+
+/* To cope with SunOS4 and other systems that lack memmove() but have bcopy(),
+define a macro for memmove() if USE_BCOPY is defined. */
+
+#ifdef USE_BCOPY
+#define memmove(a, b, c) bcopy(b, a, c)
+#endif
+
+/* Standard C headers plus the external interface definition */
+
+#include <ctype.h>
+#include <limits.h>
+#include <setjmp.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "pcre.h"
+
+/* Private options flags start at the most significant end of the two bytes.
+The public options defined in pcre.h start at the least significant end. Make
+sure they don't overlap! */
+
+#define PCRE_FIRSTSET           0x8000  /* first_char is set */
+#define PCRE_STARTLINE          0x4000  /* start after \n for multiline */
+#define PCRE_COMPILED_CASELESS  0x2000  /* like it says */
+
+/* Options for the "extra" block produced by pcre_study(). */
+
+#define PCRE_STUDY_CASELESS 0x01     /* study was caseless */
+#define PCRE_STUDY_MAPPED   0x02     /* a map of starting chars exists */
+
+/* Masks for identifying the public options: all permitted at compile time,
+only some permitted at run or study time. */
+
+#define PUBLIC_OPTIONS \
+  (PCRE_CASELESS|PCRE_EXTENDED|PCRE_ANCHORED|PCRE_MULTILINE| \
+   PCRE_DOTALL|PCRE_DOLLAR_ENDONLY|PCRE_EXTRA)
+
+#define PUBLIC_EXEC_OPTIONS \
+  (PCRE_CASELESS|PCRE_ANCHORED|PCRE_MULTILINE|PCRE_NOTBOL|PCRE_NOTEOL| \
+   PCRE_DOTALL|PCRE_DOLLAR_ENDONLY)
+
+#define PUBLIC_STUDY_OPTIONS (PCRE_CASELESS)
+
+/* Magic number to provide a small check against being handed junk. */
+
+#define MAGIC_NUMBER  0x50435245   /* 'PCRE' */
+
+/* Miscellaneous definitions */
+
+typedef int BOOL;
+
+#define FALSE   0
+#define TRUE    1
+
+/* These are escaped items that aren't just an encoding of a particular data
+value such as \n. They must have non-zero values, as check_escape() returns
+their negation. Also, they must appear in the same order as in the opcode
+definitions below, up to ESC_Z. The final one must be ESC_REF as subsequent
+values are used for \1, \2, \3, etc. There is a test in the code for an escape
+greater than ESC_b and less than ESC_X to detect the types that may be
+repeated. If any new escapes are put in-between that don't consume a character,
+that code will have to change. */
+
+enum { ESC_A = 1, ESC_B, ESC_b, ESC_D, ESC_d, ESC_S, ESC_s, ESC_W, ESC_w,
+
+                    /* These are not Perl escapes, so can't appear in the */
+       ESC_X,       /* simple table-lookup because they must be conditional */
+                    /* on PCRE_EXTRA. */
+       ESC_Z,
+       ESC_REF };
+
+/* Opcode table: OP_BRA must be last, as all values >= it are used for brackets
+that extract substrings. Starting from 1 (i.e. after OP_END), the values up to
+OP_EOL must correspond in order to the list of escapes immediately above. */
+
+enum {
+  OP_END,            /* End of pattern */
+
+  /* Values corresponding to backslashed metacharacters */
+
+  OP_SOD,            /* Start of data: \A */
+  OP_NOT_WORD_BOUNDARY,  /* \B */
+  OP_WORD_BOUNDARY,      /* \b */
+  OP_NOT_DIGIT,          /* \D */
+  OP_DIGIT,              /* \d */
+  OP_NOT_WHITESPACE,     /* \S */
+  OP_WHITESPACE,         /* \s */
+  OP_NOT_WORDCHAR,       /* \W */
+  OP_WORDCHAR,           /* \w */
+  OP_CUT,            /* The analogue of Prolog's "cut" operation (extension) */
+  OP_EOD,            /* End of data: or \Z. This must always be the last
+                        of the backslashed meta values. */
+
+  OP_CIRC,           /* Start of line - varies with multiline switch */
+  OP_DOLL,           /* End of line - varies with multiline switch */
+  OP_ANY,            /* Match any character */
+  OP_CHARS,          /* Match string of characters */
+  OP_NOT,            /* Match anything but the following char */
+
+  OP_STAR,           /* The maximizing and minimizing versions of */
+  OP_MINSTAR,        /* all these opcodes must come in pairs, with */
+  OP_PLUS,           /* the minimizing one second. */
+  OP_MINPLUS,        /* This first set applies to single characters */
+  OP_QUERY,
+  OP_MINQUERY,
+  OP_UPTO,           /* From 0 to n matches */
+  OP_MINUPTO,
+  OP_EXACT,          /* Exactly n matches */
+
+  OP_NOTSTAR,        /* The maximizing and minimizing versions of */
+  OP_NOTMINSTAR,     /* all these opcodes must come in pairs, with */
+  OP_NOTPLUS,        /* the minimizing one second. */
+  OP_NOTMINPLUS,     /* This first set applies to "not" single characters */
+  OP_NOTQUERY,
+  OP_NOTMINQUERY,
+  OP_NOTUPTO,        /* From 0 to n matches */
+  OP_NOTMINUPTO,
+  OP_NOTEXACT,       /* Exactly n matches */
+
+  OP_TYPESTAR,       /* The maximizing and minimizing versions of */
+  OP_TYPEMINSTAR,    /* all these opcodes must come in pairs, with */
+  OP_TYPEPLUS,       /* the minimizing one second. These codes must */
+  OP_TYPEMINPLUS,    /* be in exactly the same order as those above. */
+  OP_TYPEQUERY,      /* This set applies to character types such as \d */
+  OP_TYPEMINQUERY,
+  OP_TYPEUPTO,       /* From 0 to n matches */
+  OP_TYPEMINUPTO,
+  OP_TYPEEXACT,      /* Exactly n matches */
+
+  OP_CRSTAR,         /* The maximizing and minimizing versions of */
+  OP_CRMINSTAR,      /* all these opcodes must come in pairs, with */
+  OP_CRPLUS,         /* the minimizing one second. These codes must */
+  OP_CRMINPLUS,      /* be in exactly the same order as those above. */
+  OP_CRQUERY,        /* These are for character classes and back refs */
+  OP_CRMINQUERY,
+  OP_CRRANGE,        /* These are different to the three seta above. */
+  OP_CRMINRANGE,
+
+  OP_CLASS,          /* Match a character class */
+  OP_REF,            /* Match a back reference */
+
+  OP_ALT,            /* Start of alternation */
+  OP_KET,            /* End of group that doesn't have an unbounded repeat */
+  OP_KETRMAX,        /* These two must remain together and in this */
+  OP_KETRMIN,        /* order. They are for groups the repeat for ever. */
+
+  OP_ASSERT,
+  OP_ASSERT_NOT,
+  OP_ONCE,           /* Once matched, don't back up into the subpattern */
+
+  OP_BRAZERO,        /* These two must remain together and in this */
+  OP_BRAMINZERO,     /* order. */
+
+  OP_BRA             /* This and greater values are used for brackets that
+                        extract substrings. */
+};
+
+/* The highest extraction number. This is limited by the number of opcodes
+left after OP_BRA, i.e. 255 - OP_BRA. We actually set it somewhat lower. */
+
+#define EXTRACT_MAX  99
+
+/* The texts of compile-time error messages are defined as macros here so that
+they can be accessed by the POSIX wrapper and converted into error codes.  Yes,
+I could have used error codes in the first place, but didn't feel like changing
+just to accommodate the POSIX wrapper. */
+
+#define ERR1  "\\ at end of pattern"
+#define ERR2  "\\c at end of pattern"
+#define ERR3  "unrecognized character follows \\"
+#define ERR4  "numbers out of order in {} quantifier"
+#define ERR5  "number too big in {} quantifier"
+#define ERR6  "missing terminating ] for character class"
+#define ERR7  "invalid escape sequence in character class"
+#define ERR8  "range out of order in character class"
+#define ERR9  "nothing to repeat"
+#define ERR10 "operand of unlimited repeat could match the empty string"
+#define ERR11 "internal error: unexpected repeat"
+#define ERR12 "unrecognized character after (?"
+#define ERR13 "too many capturing parenthesized sub-patterns"
+#define ERR14 "missing )"
+#define ERR15 "back reference to non-existent subpattern"
+#define ERR16 "erroffset passed as NULL"
+#define ERR17 "unknown option bit(s) set"
+#define ERR18 "missing ) after comment"
+#define ERR19 "too many sets of parentheses"
+#define ERR20 "regular expression too large"
+#define ERR21 "failed to get memory"
+#define ERR22 "unmatched brackets"
+#define ERR23 "internal error: code overflow"
+
+/* All character handling must be done as unsigned characters. Otherwise there
+are problems with top-bit-set characters and functions such as isspace().
+However, we leave the interface to the outside world as char *, because that
+should make things easier for callers. We define a short type for unsigned char
+to save lots of typing. I tried "uchar", but it causes problems on Digital
+Unix, where it is defined in sys/types, so use "uschar" instead. */
+
+typedef unsigned char uschar;
+
+/* The real format of the start of the pcre block; the actual code vector
+runs on as long as necessary after the end. */
+
+typedef struct real_pcre {
+  unsigned int  magic_number;
+  unsigned short int options;
+  unsigned char top_bracket;
+  unsigned char top_backref;
+  unsigned char first_char;
+  unsigned char code[1];
+} real_pcre;
+
+/* The real format of the extra block returned by pcre_study(). */
+
+typedef struct real_pcre_extra {
+  unsigned char options;
+  unsigned char start_bits[32];
+} real_pcre_extra;
+
+/* Global tables from chartables.c */
+
+extern uschar pcre_lcc[];
+extern uschar pcre_fcc[];
+extern uschar pcre_cbits[];
+extern uschar pcre_ctypes[];
+
+/* Bit definitions for entries in pcre_ctypes[]. */
+
+#define ctype_space   0x01
+#define ctype_letter  0x02
+#define ctype_digit   0x04
+#define ctype_xdigit  0x08
+#define ctype_word    0x10   /* alphameric or '_' */
+#define ctype_meta    0x80   /* regexp meta char or zero (end pattern) */
+
+/* Offsets for the bitmap tables */
+
+#define cbit_digit    0
+#define cbit_letter  32
+#define cbit_word    64
+#define cbit_space   96
+#define cbit_length 128      /* Length of the cbits table */
+
+/* End of internal.h */
diff --git a/maketables.c b/maketables.c
new file mode 100644
index 0000000..26a1319
--- /dev/null
+++ b/maketables.c
@@ -0,0 +1,157 @@
+/*************************************************
+*      Perl-Compatible Regular Expressions       *
+*************************************************/
+
+/*
+PCRE is a library of functions to support regular expressions whose syntax
+and semantics are as close as possible to those of the Perl 5 language.
+
+Written by: Philip Hazel <ph10@cam.ac.uk>
+
+           Copyright (c) 1997 University of Cambridge
+
+-----------------------------------------------------------------------------
+Permission is granted to anyone to use this software for any purpose on any
+computer system, and to redistribute it freely, subject to the following
+restrictions:
+
+1. This software is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+
+2. The origin of this software must not be misrepresented, either by
+   explicit claim or by omission.
+
+3. Altered versions must be plainly marked as such, and must not be
+   misrepresented as being the original software.
+-----------------------------------------------------------------------------
+
+See the file Tech.Notes for some information on the internals.
+*/
+
+
+/* This is a support program to generate the file chartables.c, containing
+character tables of various kinds. They are built according to the local C
+locale. */
+
+#include <ctype.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "internal.h"
+
+int main(void)
+{
+int i;
+unsigned char cbits[cbit_length];
+
+printf(
+  "/*************************************************\n"
+  "*      Perl-Compatible Regular Expressions       *\n"
+  "*************************************************/\n\n"
+  "/* This file is automatically written by the makechartables auxiliary \n"
+  "program. If you edit it by hand, you might like to edit the Makefile to \n"
+  "prevent its ever being regenerated. */\n\n"
+  "/* This table is a lower casing table. */\n\n"
+  "unsigned char pcre_lcc[] = {\n");
+
+printf("  ");
+for (i = 0; i < 256; i++)
+  {
+  if ((i & 7) == 0 && i != 0) printf("\n  ");
+  printf("%3d", tolower(i));
+  if (i != 255) printf(",");
+  }
+printf(" };\n\n");
+
+printf(
+  "/* This table is a case flipping table. */\n\n"
+  "unsigned char pcre_fcc[] = {\n");
+
+printf("  ");
+for (i = 0; i < 256; i++)
+  {
+  if ((i & 7) == 0 && i != 0) printf("\n  ");
+  printf("%3d", islower(i)? toupper(i) : tolower(i));
+  if (i != 255) printf(",");
+  }
+printf(" };\n\n");
+
+printf(
+  "/* This table contains bit maps for digits, letters, 'word' chars, and\n"
+  "white space. Each map is 32 bytes long and the bits run from the least\n"
+  "significant end of each byte. */\n\n"
+  "unsigned char pcre_cbits[] = {\n");
+
+memset(cbits, 0, sizeof(cbits));
+
+for (i = 0; i < 256; i++)
+  {
+  if (isdigit(i)) cbits[cbit_digit  + i/8] |= 1 << (i&7);
+  if (isalpha(i)) cbits[cbit_letter + i/8] |= 1 << (i&7);
+  if (isalnum(i) || i == '_')
+                  cbits[cbit_word   + i/8] |= 1 << (i&7);
+  if (isspace(i)) cbits[cbit_space  + i/8] |= 1 << (i&7);
+  }
+
+printf("  ");
+for (i = 0; i < cbit_length; i++)
+  {
+  if ((i & 7) == 0 && i != 0)
+    {
+    if ((i & 31) == 0) printf("\n");
+    printf("\n  ");
+    }
+  printf("0x%02x", cbits[i]);
+  if (i != cbit_length - 1) printf(",");
+  }
+printf(" };\n\n");
+
+printf(
+  "/* This table identifies various classes of character by individual bits:\n"
+  "  0x%02x   white space character\n"
+  "  0x%02x   letter\n"
+  "  0x%02x   decimal digit\n"
+  "  0x%02x   hexadecimal digit\n"
+  "  0x%02x   alphanumeric or '_'\n"
+  "  0x%02x   regular expression metacharacter or binary zero\n*/\n\n",
+  ctype_space, ctype_letter, ctype_digit, ctype_xdigit, ctype_word,
+  ctype_meta);
+
+printf("unsigned char pcre_ctypes[] = {\n");
+
+printf("  ");
+for (i = 0; i < 256; i++)
+  {
+  int x = 0;
+  if (isspace(i)) x += ctype_space;
+  if (isalpha(i)) x += ctype_letter;
+  if (isdigit(i)) x += ctype_digit;
+  if (isxdigit(i)) x += ctype_xdigit;
+  if (isalnum(i) || i == '_') x += ctype_word;
+  if (strchr("*+?{^.$|()[", i) != 0) x += ctype_meta;
+
+  if ((i & 7) == 0 && i != 0)
+    {
+    printf(" /* ");
+    if (isprint(i-8)) printf(" %c -", i-8);
+      else printf("%3d-", i-8);
+    if (isprint(i-1)) printf(" %c ", i-1);
+      else printf("%3d", i-1);
+    printf(" */\n  ");
+    }
+  printf("0x%02x", x);
+  if (i != 255) printf(",");
+  }
+
+printf("};/* ");
+if (isprint(i-8)) printf(" %c -", i-8);
+  else printf("%3d-", i-8);
+if (isprint(i-1)) printf(" %c ", i-1);
+  else printf("%3d", i-1);
+printf(" */\n\n/* End of chartables.c */\n");
+
+return 0;
+}
+
+/* End of maketables.c */
diff --git a/pcre.3 b/pcre.3
new file mode 100644
index 0000000..573bacb
--- /dev/null
+++ b/pcre.3
@@ -0,0 +1,1017 @@
+.TH PCRE 3
+.SH NAME
+pcre - Perl-compatible regular expressions.
+.SH SYNOPSIS
+.B #include <pcre.h>
+.PP
+.SM
+.br
+.B pcre *pcre_compile(const char *\fIpattern\fR, int \fIoptions\fR,
+.ti +5n
+.B char **\fIerrptr\fR, int *\fIerroffset\fR);
+.PP
+.br
+.B pcre_extra *pcre_study(const pcre *\fIcode\fR, int \fIoptions\fR,
+.ti +5n
+.B char **\fIerrptr\fR);
+.PP
+.br
+.B int pcre_exec(const pcre *\fIcode\fR, "const pcre_extra *\fIextra\fR,"
+.ti +5n
+.B "const char *\fIsubject\fR," int \fIlength\fR, int \fIoptions\fR,
+.ti +5n
+.B int *\fIovector\fR, int \fIovecsize\fR);
+.PP
+.br
+.B int pcre_info(const pcre *\fIcode\fR, int *\fIoptptr\fR, int
+.B *\fIfirstcharptr\fR);
+.PP
+.br
+.B char *pcre_version(void);
+.PP
+.br
+.B void *(*pcre_malloc)(size_t);
+.PP
+.br
+.B void (*pcre_free)(void *);
+.PP
+.br
+.B unsigned char *pcre_cbits[128];
+.PP
+.br
+.B unsigned char *pcre_ctypes[256];
+.PP
+.br
+.B unsigned char *pcre_fcc[256];
+.PP
+.br
+.B unsigned char *pcre_lcc[256];
+
+
+
+.SH DESCRIPTION
+The PCRE library is a set of functions that implement regular expression
+pattern matching using the same syntax and semantics as Perl 5, with just a few
+differences (see below). The current implementation corresponds to Perl 5.004.
+
+PCRE has its own native API, which is described in this man page. There is also
+a set of wrapper functions that correspond to the POSIX API. See
+\fBpcreposix (3)\fR.
+
+The three functions \fBpcre_compile()\fR, \fBpcre_study()\fR, and
+\fBpcre_exec()\fR are used for compiling and matching regular expressions. The
+function \fBpcre_info()\fR is used to find out information about a compiled
+pattern, while the function \fBpcre_version()\fR returns a pointer to a string
+containing the version of PCRE and its date of release.
+
+The global variables \fBpcre_malloc\fR and \fBpcre_free\fR initially contain
+the entry points of the standard \fBmalloc()\fR and \fBfree()\fR functions
+respectively. PCRE calls the memory management functions via these variables,
+so a calling program can replace them if it wishes to intercept the calls. This
+should be done before calling any PCRE functions.
+
+The other global variables are character tables. They are initialized when PCRE
+is compiled, from source that is generated by reference to the C character type
+functions, but which the maintainer of PCRE is free to modify. In principle
+they could also be modified at runtime. See PCRE's README file for more
+details.
+
+
+.SH MULTI-THREADING
+The PCRE functions can be used in multi-threading applications, with the
+proviso that the character tables and the memory management functions pointed
+to by \fBpcre_malloc\fR and \fBpcre_free\fR will be shared by all threads.
+
+The compiled form of a regular expression is not altered during matching, so
+the same compiled pattern can safely be used by several threads at once.
+
+
+.SH COMPILING A PATTERN
+The function \fBpcre_compile()\fR is called to compile a pattern into an
+internal form. The pattern is a C string terminated by a binary zero, and
+is passed in the argument \fIpattern\fR. A pointer to the compiled code block
+is returned. The \fBpcre\fR type is defined for this for convenience, but in
+fact \fBpcre\fR is just a typedef for \fBvoid\fR, since the contents of the
+block are not defined.
+.PP
+The size of a compiled pattern is roughly proportional to the length of the
+pattern string, except that each character class (other than those containing
+just a single character, negated or not) requires 33 bytes, and repeat
+quantifiers with a minimum greater than one or a bounded maximum cause the
+relevant portions of the compiled pattern to be replicated.
+.PP
+The \fIoptions\fR argument contains independent bits that affect the
+compilation. It should be zero if no options are required. Those options that
+are compabible with Perl can also be set at compile time from within the
+pattern (see the detailed description of regular expressions below) and all
+options except PCRE_EXTENDED and PCRE_EXTRA can be set at the time of matching.
+.PP
+If \fIerrptr\fR is NULL, \fBpcre_compile()\fR returns NULL immediately.
+Otherwise, if compilation of a pattern fails, \fBpcre_compile()\fR returns
+NULL, and sets the variable pointed to by \fIerrptr\fR to point to a textual
+error message.
+
+The offset from the start of the pattern to the character where the error was
+discovered is placed in the variable pointed to by \fIerroffset\fR, which must
+not be NULL. If it is, an immediate error is given.
+.PP
+The following option bits are defined in the header file:
+
+  PCRE_ANCHORED
+
+If this bit is set, the pattern is forced to be "anchored", that is, it is
+constrained to match only at the start of the string which is being searched
+(the "subject string"). This effect can also be achieved by appropriate
+constructs in the pattern itself, which is the only way to do it in Perl.
+
+  PCRE_CASELESS
+
+If this bit is set, letters in the pattern match both upper and lower case
+letters in any subject string. It is equivalent to Perl's /i option.
+
+  PCRE_DOLLAR_ENDONLY
+
+If this bit is set, a dollar metacharacter in the pattern matches only at the
+end of the subject string. By default, it also matches immediately before the
+final character if it is a newline (but not before any other newlines). The
+PCRE_DOLLAR_ENDONLY option is ignored if PCRE_MULTILINE is set. There is no
+equivalent to this option in Perl.
+
+  PCRE_DOTALL
+
+If this bit is set, a dot metacharater in the pattern matches all characters,
+including newlines. By default, newlines are excluded. This option is
+equivalent to Perl's /s option. A negative class such as [^a] always matches a
+newline character, independent of the setting of this option.
+
+  PCRE_EXTENDED
+
+If this bit is set, whitespace characters in the pattern are totally ignored
+except when escaped or inside a character class, and characters between an
+unescaped # outside a character class and the next newline character,
+inclusive, are also ignored. This is equivalent to Perl's /x option, and makes
+it possible to include comments inside complicated patterns.
+
+  PCRE_MULTILINE
+
+By default, PCRE treats the subject string as consisting of a single "line" of
+characters (even if it actually contains several newlines). The "start of line"
+metacharacter (^) matches only at the start of the string, while the "end of
+line" metacharacter ($) matches only at the end of the string, or before a
+terminating newline. This is the same as Perl.
+
+When PCRE_MULTILINE it is set, the "start of line" and "end of line" constructs
+match immediately following or immediately before any newline in the subject
+string, respectively, as well as at the very start and end. This is equivalent
+to Perl's /m option. If there are no "\\n" characters in a subject string, or
+no occurrences of ^ or $ in a pattern, setting PCRE_MULTILINE has no
+effect.
+
+  PCRE_EXTRA
+
+This option turns on additional functionality of PCRE that is incompatible with
+Perl. Any backslash in a pattern that is followed by a letter that has no
+special meaning causes an error, thus reserving these combinations for future
+expansion. By default, as in Perl, a backslash followed by a letter with no
+special meaning is treated as a literal. There are two extra features currently
+provided, and both are in some sense experimental additions that are useful for
+influencing the progress of a match.
+
+  (1) The sequence \\X inserts a Prolog-like "cut" into the expression.
+
+  (2) Once a subpattern enclosed in (?>subpat) brackets has matched,
+      backtracking never goes back into the pattern.
+
+See below for further details of both of these.
+
+
+
+.SH STUDYING A PATTERN
+When a pattern is going to be used several times, it is worth spending more
+time analyzing it in order to speed up the time taken for matching. The
+function \fBpcre_study()\fR takes a pointer to a compiled pattern as its first
+argument, and returns a pointer to a \fBpcre_extra\fR block (another \fBvoid\fR
+typedef) containing additional information about the pattern; this can be
+passed to \fBpcre_exec()\fR. If no additional information is available, NULL
+is returned.
+
+The second argument contains option bits. The only one currently supported is
+PCRE_CASELESS. It forces the studying to be done in a caseless manner, even if
+the original pattern was compiled without PCRE_CASELESS. When the result of
+\fBpcre_study()\fR is passed to \fBpcre_exec()\fR, it is used only if its
+caseless state is the same as that of the matching process. A pattern that is
+compiled without PCRE_CASELESS can be studied with and without PCRE_CASELESS,
+and the appropriate data passed to \fBpcre_exec()\fR with and without the
+PCRE_CASELESS flag.
+
+The third argument for \fBpcre_study()\fR is a pointer to an error message. If
+studying succeeds (even if no data is returned), the variable it points to is
+set to NULL. Otherwise it points to a textual error message.
+
+At present, studying a pattern is useful only for non-anchored patterns that do
+not have a single fixed starting character. A bitmap of possible starting
+characters is created.
+
+
+.SH MATCHING A PATTERN
+The function \fBpcre_exec()\fR is called to match a subject string against a
+pre-compiled pattern, which is passed in the \fIcode\fR argument. If the
+pattern has been studied, the result of the study should be passed in the
+\fIextra\fR argument. Otherwise this must be NULL.
+
+The subject string is passed as a pointer in \fIsubject\fR and a length in
+\fIlength\fR. Unlike the pattern string, it may contain binary zero characters.
+
+The options PCRE_ANCHORED, PCRE_CASELESS, PCRE_DOLLAR_ENDONLY, PCRE_DOTALL, and
+PCRE_MULTILINE can be passed in the \fIoptions\fR argument, whose unused bits
+must be zero. However, if a pattern is compiled with any of these options, they
+cannot be unset when it is obeyed.
+
+There are also two further options that can be set only at matching time:
+
+  PCRE_NOTBOL
+
+The first character of the string is not the beginning of a line, so the
+circumflex metacharacter should not match before it. Setting this without
+PCRE_MULTILINE (at either compile or match time) causes circumflex never to
+match.
+
+  PCRE_NOTEOL
+
+The end of the string is not the end of a line, so the dollar metacharacter
+should not match it. Setting this without PCRE_MULTILINE (at either compile or
+match time) causes dollar never to match.
+
+In general, a pattern matches a certain portion of the subject, and in
+addition, further substrings from the subject may be picked out by parts of the
+pattern. Following the usage in Jeffrey Friedl's book, this is called
+"capturing" in what follows, and the phrase "capturing subpattern" is used for
+a fragment of a pattern that picks out a substring. PCRE supports several other
+kinds of parenthesized subpattern that do not cause substrings to be captured.
+
+Captured substrings are returned to the caller via a vector of integer offsets
+whose address is passed in \fIovector\fR. The number of elements in the vector
+is passed in \fIovecsize\fR. This should always be an even number, because the
+elements are used in pairs. If an odd number is passed, it is rounded down.
+
+The first element of a pair is set to the offset of the first character in a
+substring, and the second is set to the offset of the first character after the
+end of a substring. The first pair, \fIovector[0]\fR and \fIovector[1]\fR,
+identify the portion of the subject string matched by the entire pattern. The
+next pair is used for the first capturing subpattern, and so on. The value
+returned by \fBpcre_exec()\fR is the number of pairs that have been set. If
+there are no capturing subpatterns, the return value from a successful match
+is 1, indicating that just the first pair of offsets has been set.
+
+It is possible for an capturing subpattern number \fIn+1\fR to match some
+part of the subject when subpattern \fIn\fR has not been used at all. For
+example, if the string "abc" is matched against the pattern "(a|(z))(bc)",
+subpatterns 1 and 3 are matched, but 2 is not. When this happens, both offset
+values corresponding to the unused subpattern are set to -1.
+
+If a capturing subpattern is matched repeatedly, it is the last portion of the
+string that it matched that gets returned.
+
+If the vector is too small to hold all the captured substrings, it is used as
+far as possible, and the function returns a value of zero. In particular, if
+the substring offsets are not of interest, \fBpcre_exec()\fR may be called with
+\fIovector\fR passed as NULL and \fIovecsize\fR as zero. However, if the
+pattern contains back references and the \fIovector\fR isn't big enough to
+remember the related substrings, PCRE has to get additional memory for use
+during matching. Thus it is usually advisable to supply an \fIovector\fR.
+
+Note that \fBpcre_info()\fR can be used to find out how many capturing
+subpatterns there are in a compiled pattern.
+
+If \fBpcre_exec()\fR fails, it returns a negative number. The following are
+defined in the header file:
+
+  PCRE_ERROR_NOMATCH        (-1)
+
+The subject string did not match the pattern.
+
+  PCRE_ERROR_BADREF         (-2)
+
+There was a back-reference in the pattern to a capturing subpattern that had
+not previously been set.
+
+  PCRE_ERROR_NULL           (-3)
+
+Either \fIcode\fR or \fIsubject\fR was passed as NULL, or \fIovector\fR was
+NULL and \fIovecsize\fR was not zero.
+
+  PCRE_ERROR_BADOPTION      (-4)
+
+An unrecognized bit was set in the \fIoptions\fR argument.
+
+  PCRE_ERROR_BADMAGIC       (-5)
+
+PCRE stores a 4-byte "magic number" at the start of the compiled code, to catch
+the case when it is passed a junk pointer. This is the error it gives when the
+magic number isn't present.
+
+  PCRE_ERROR_UNKNOWN_NODE   (-6)
+
+While running the pattern match, an unknown item was encountered in the
+compiled pattern. This error could be caused by a bug in PCRE or by overwriting
+of the compiled pattern.
+
+  PCRE_ERROR_NOMEMORY       (-7)
+
+If a pattern contains back references, but the \fIovector\fR that is passed to
+\fBpcre_exec()\fR is not big enough to remember the referenced substrings, PCRE
+gets a block of memory at the start of matching to use for this purpose. If the
+call via \fBpcre_malloc()\fR fails, this error is given. The memory is freed at
+the end of matching.
+
+
+.SH INFORMATION ABOUT A PATTERN
+The \fBpcre_info()\fR function returns information about a compiled pattern.
+Its yield is the number of capturing subpatterns, or one of the following
+negative numbers:
+
+  PCRE_ERROR_NULL       the argument \fIcode\fR was NULL
+  PCRE_ERROR_BADMAGIC   the "magic number" was not found
+
+If the \fIoptptr\fR argument is not NULL, a copy of the options with which the
+pattern was compiled is placed in the integer it points to.
+
+If the \fIfirstcharptr\fR argument is not NULL, is is used to pass back
+information about the first character of any matched string. If there is a
+fixed first character, e.g. from a pattern such as (cat|cow|coyote), then it is
+returned in the integer pointed to by \fIfirstcharptr\fR. Otherwise, if the
+pattern was compiled with the PCRE_MULTILINE option, and every branch started
+with "^", then -1 is returned, indicating that the pattern will match at the
+start of a subject string or after any "\\n" within the string. Otherwise -2 is
+returned.
+
+
+.SH LIMITATIONS
+There are some size limitations in PCRE but it is hoped that they will never in
+practice be relevant.
+The maximum length of a compiled pattern is 65539 (sic) bytes.
+All values in repeating quantifiers must be less than 65536.
+The maximum number of capturing subpatterns is 99.
+The maximum number of all parenthesized subpatterns, including capturing
+subpatterns and assertions, is 200.
+
+The maximum length of a subject string is the largest positive number that an
+integer variable can hold. However, PCRE uses recursion to handle subpatterns
+and indefinite repetition. This means that the available stack space may limit
+the size of a subject string that can be processed by certain patterns.
+
+
+.SH DIFFERENCES FROM PERL
+The differences described here are with respect to Perl 5.004.
+
+1. By default, a whitespace character is any character that the C library
+function \fBisspace()\fR recognizes, though it is possible to compile PCRE with
+alternative character type tables. Normally \fBisspace()\fR matches space,
+formfeed, newline, carriage return, horizontal tab, and vertical tab. Perl 5
+no longer includes vertical tab in its set of whitespace characters. The \\v
+escape that was in the Perl documentation for a long time was never in fact
+recognized. However, the character itself was treated as whitespace at least
+up to 5.002. In 5.004 it does not match \\s.
+
+2. PCRE does not allow repeat quantifiers on lookahead assertions. Perl permits
+them, but they do not mean what you might think. For example, "(?!a){3}" does
+not assert that the next three characters are not "a". It just asserts that the
+next character is not "a" three times.
+
+3. Capturing subpatterns that occur inside negative lookahead assertions are
+counted, but their entries in the offsets vector are never set. Perl sets its
+numerical variables from any such patterns that are matched before the
+assertion fails to match something (thereby succeeding), but only if the
+negative lookahead assertion contains just one branch.
+
+4. Though binary zero characters are supported in the subject string, they are
+not allowed in a pattern string because it is passed as a normal C string,
+terminated by zero. The escape sequence "\\0" can be used in the pattern to
+represent a binary zero.
+
+5. The following Perl escape sequences are not supported: \\l, \\u, \\L, \\U,
+\\E, \\Q. In fact these are implemented by Perl's general string-handling and
+are not part of its pattern matching engine.
+
+6. The Perl \\G assertion is not supported as it is not relevant to single
+pattern matches.
+
+7. If a backreference can never be matched, PCRE diagnoses an error. In a case
+like
+
+  /(123)\\2/
+
+the error occurs at compile time. Perl gives no compile time error; version
+5.004 either always fails to match, or gives a segmentation fault at runtime.
+In more complicated cases such as
+
+  /(1)(2)(3)(4)(5)(6)(7)(8)(9)(10\\10)/
+
+PCRE returns PCRE_ERROR_BADREF at run time. Perl always fails to match.
+
+8. PCRE provides some extensions to the Perl regular expression facilities:
+
+(a) If PCRE_DOLLAR_ENDONLY is set and PCRE_MULTILINE is not set, the $ meta-
+character matches only at the very end of the string.
+
+(b) If PCRE_EXTRA is set, the \\X assertion (a Prolog-like "cut") is
+recognized, and a backslash followed by a letter with no special meaning is
+faulted. There is also a new kind of parenthesized subpattern starting with (?>
+which has a block on backtracking into it once it has matched.
+
+
+.SH REGULAR EXPRESSION DETAILS
+The syntax and semantics of the regular expressions supported by PCRE are
+described below. Regular expressions are also described in the Perl
+documentation and in a number of other books, some of which have copious
+examples. Jeffrey Friedl's "Mastering Regular Expressions", published by
+O'Reilly (ISBN 1-56592-257-3), covers them in great detail. The description
+here is intended as reference documentation.
+
+A regular expression is a pattern that is matched against a subject string from
+left to right. Most characters stand for themselves in a pattern, and match the
+corresponding characters in the subject. As a trivial example, the pattern
+
+  The quick brown fox
+
+matches a portion of a subject string that is identical to itself. The power of
+regular expressions comes from the ability to include alternatives and
+repetitions in the pattern. These are encoded in the pattern by the use of
+\fImeta-characters\fR, which do not stand for themselves but instead are
+interpreted in some special way.
+
+There are two different sets of meta-characters: those that are recognized
+anywhere in the pattern except within square brackets, and those that are
+recognized in square brackets. Outside square brackets, the meta-characters are
+as follows:
+
+  \\      general escape character with several uses
+  ^      assert start of subject (or line, in multiline mode)
+  $      assert end of subject (or line, in multiline mode)
+  .      match any character except newline (by default)
+  [      start character class definition
+  |      start of alternative branch
+  (      start subpattern
+  )      end subpattern
+  ?      extends the meaning of (
+         also 0 or 1 quantifier
+         also quantifier minimizer
+  *      0 or more quantifier
+  +      1 or more quantifier
+  {      start min/max quantifier
+
+Part of a pattern that is in square brackets is called a "character class". In
+a character class the only meta-characters are:
+
+  \\      general escape character
+  ^      negate the class, but only if the first character
+  -      indicates character range
+  ]      terminates the character class
+
+The following sections describe the use of each of the meta-characters.
+
+
+.SH BACKSLASH
+The backslash character has several uses. Firstly, if it is followed by a
+non-alphameric character, it takes away any special meaning that character may
+have. This use of backslash as an escape character applies both inside and
+outside character classes.
+
+For example, if you want to match a "*" character, you write "\\*" in the
+pattern. This applies whether or not the following character would otherwise be
+interpreted as a meta-character, so it is always safe to precede a
+non-alphameric with "\\" to specify that it stands for itself. In particular,
+if you want to match a backslash, you write "\\\\".
+
+If a pattern is compiled with the PCRE_EXTENDED option, whitespace in the
+pattern and characters between a "#" outside a character class and the next
+newline character are ignored. An escaping backslash can be used to include a
+whitespace or "#" character as part of the pattern.
+
+A second use of backslash provides a way of encoding non-printing characters
+in patterns in a visible manner. There is no restriction on the appearance of
+non-printing characters, apart from the binary zero that terminates a pattern,
+but when a pattern is being prepared by text editing, it is usually easier to
+use one of the following escape sequences than the binary character it
+represents:
+
+  \\a     alarm, that is, the BEL character (hex 07)
+  \\cx    "control-x", where x is any character
+  \\e     escape (hex 1B)
+  \\f     formfeed (hex 0C)
+  \\n     newline (hex 0A)
+  \\r     carriage return (hex 0D)
+  \\t     tab (hex 09)
+  \\xhh   character with hex code hh
+  \\ddd   character with octal code ddd or backreference
+
+The precise effect of "\\cx" is as follows: if "x" is a lower case letter, it
+is converted to upper case. Then bit 6 of the character (hex 40) is inverted.
+Thus "\\cz" becomes hex 1A, but "\\c{" becomes hex 3B, while "\\c;" becomes hex
+7B.
+
+After "\\x", up to two hexadecimal digits are read (letters can be in upper or
+lower case).
+
+After "\\0" up to two further octal digits are read. In both cases, if there
+are fewer than two digits, just those that are present are used. Thus the
+sequence "\\0\\x\\07" specifies two binary zeros followed by a BEL character.
+Make sure you supply two digits if the character that follows could otherwise
+be taken as another digit.
+
+The handling of a backslash followed by a digit other than 0 is complicated.
+Outside a character class, PCRE reads it and any following digits as a decimal
+number. If the number is less than 10, or if there have been at least that many
+previous capturing left parentheses in the expression, the entire sequence is
+taken as a \fIback reference\fR. A description of how this works is given
+later, following the discussion of parenthesized subpatterns.
+
+Inside a character class, or if the decimal number is greater than 9 and there
+have not been that many capturing subpatterns, PCRE re-reads up to three octal
+digits following the backslash, and generates a single byte from the least
+significant 8 bits of the value. Any subsequent digits stand for themselves.
+For example:
+
+  \\040   is another way of writing a space
+  \\40    is the same, provided there are fewer than 40
+            previous capturing subpatterns
+  \\7     is always a back reference
+  \\11    might be a back reference, or another way of
+            writing a tab
+  \\011   is always a tab
+  \\0113  is a tab followed by the character "3"
+  \\113   is the character with octal code 113 (since there
+            can be no more than 99 back references)
+  \\377   is a byte consisting entirely of 1 bits
+  \\81    is either a back reference, or a binary zero
+            followed by the two characters "8" and "1"
+
+Note that octal values of 100 or greater must not be introduced by a leading
+zero, because no more than three octal digits are ever read.
+
+All the sequences that define a single byte value can be used both inside and
+outside character classes. In addition, inside a character class, the sequence
+"\\b" is interpreted as the backspace character (hex 08). Outside a character
+class it has a different meaning (see below).
+
+The third use of backslash is for specifying generic character types:
+
+  \\d     any decimal digit
+  \\D     any character that is not a decimal digit
+  \\s     any whitespace character
+  \\S     any character that is not a whitespace character
+  \\w     any "word" character
+  \\W     any "non-word" character
+
+Each pair of escape sequences partitions the complete set of characters into
+two disjoint sets. Any given character matches one, and only one, of each pair.
+
+A "word" character is any letter or digit or the underscore character, that is,
+any character which can be part of a Perl "word". These character type
+sequences can appear both inside and outside character classes. They each match
+one character of the appropriate type. If the current matching point is at the
+end of the subject string, all of them fail, since there is no character to
+match.
+
+The fourth use of backslash is for certain assertions. An assertion specifies a
+condition that has to be met at a particular point in a match, without
+consuming any characters from the subject string. The backslashed assertions
+are
+
+  \\b     word boundary
+  \\B     not a word boundary
+  \\A     start of subject (independent of multiline mode)
+  \\Z     end of subject (independent of multiline mode)
+
+Assertions may not appear in character classes (but note that "\\b" has a
+different meaning, namely the backspace character, inside a character class).
+
+A word boundary is a position in the subject string where the current character
+and the previous character do not both match "\\w" or "\\W" (i.e. one matches
+"\\w" and the other matches "\\W"), or the start or end of the string if the
+first or last character matches "\\w", respectively. More complicated
+assertions are also supported (see below).
+
+The "\\A" and "\\Z" assertions differ from the traditional "^" and "$"
+(described below) in that they only ever match at the very start and end of the
+subject string, respectively, whatever options are set.
+
+When the PCRE_EXTRA flag is set on a call to \fBpcre_compile()\fR, the
+additional assertion \\X, which has no equivalent in Perl, is recognized.
+This operates like the "cut" operation in Prolog: it prevents the matching
+operation from backtracking past it. For example, if the expression
+
+  .*/foo
+
+is matched against the string "/foo/this/is/not" then after the initial greedy
+.* has swallowed the whole string, it keeps backtracking right the way to the
+beginning before failing. If, on the other hand, the expression is
+
+  .*/\\Xfoo
+
+then once it has discovered that "/not" is not "/foo", backtracking ceases, and
+the match fails. See also the section on "once-only" subpatterns below.
+
+
+
+.SH CIRCUMFLEX AND DOLLAR
+Outside a character class, the circumflex character is an assertion which is
+true only if the current matching point is at the start of the subject string,
+in the default matching mode. Inside a character class, circumflex has an
+entirely different meaning (see below).
+
+Circumflex need not be the first character of the pattern if a number of
+alternatives are involved, but it should be the first thing in each alternative
+in which it appears if the pattern is ever to match that branch. If all
+possible alternatives start with a circumflex, that is, if the pattern is
+constrained to match only at the start of the subject, it is said to be an
+"anchored" pattern. (There are also other constructs that can cause a pattern
+to be anchored.)
+
+A dollar character is an assertion which is true only if the current matching
+point is at the end of the subject string, or immediately before a newline
+character that is the last character in the string (by default). Dollar need
+not be the last character of the pattern if a number of alternatives are
+involved, but it should be the last item in any branch in which it appears.
+Dollar has no special meaning in a character class.
+
+The meaning of dollar can be changed so that it matches only at the very end of
+the string, by setting the PCRE_DOLLAR_ENDONLY option at compile or matching
+time.
+
+The meanings of the circumflex and dollar characters are changed if the
+PCRE_MULTILINE option is set at compile or matching time. When this is the
+case, they match immediately after and immediately before an internal "\\n"
+character, respectively, in addition to matching at the start and end of the
+subject string. For example, the pattern /^abc$/ matches the subject string
+"def\\nabc" in multiline mode, but not otherwise. Consequently, patterns that
+are anchored in single line mode because all branches start with "^" are not
+anchored in multiline mode. The PCRE_DOLLAR_ENDONLY option is ignored if
+PCRE_MULTILINE is set.
+
+Note that the sequences "\\A" and "\\Z" can be used to match the start and end
+of the subject in both modes, and if all branches of a pattern start with "\\A"
+is it always anchored.
+
+
+.SH FULL STOP (PERIOD, DOT)
+Outside a character class, a dot in the pattern matches any one character in
+the subject, including a non-printing character, but not (by default) newline.
+If the PCRE_DOTALL option is set, then dots match newlines as well. The
+handling of dot is entirely independent of the handling of circumflex and
+dollar, the only relationship being that they both involve newline characters.
+Dot has no special meaning in a character class.
+
+
+.SH SQUARE BRACKETS
+An opening square bracket introduces a character class, terminated by a closing
+square bracket. A closing square bracket on its own is not special. If a
+closing square bracket is required as a member of the class, it should be the
+first data character in the class (after an initial circumflex, if present) or
+escaped with \\.
+
+A character class matches a single character in the subject; the character must
+be in the set of characters defined by the class, unless the first character in
+the class is a circumflex, in which case the subject character must not be in
+the set defined by the class. If a circumflex is actually required as a member
+of the class, ensure it is not the first character, or escape it with \\.
+
+For example, the character class [aeiou] matches any lower case vowel, while
+[^aeiou] matches any character that is not a lower case vowel. Note that a
+circumflex is just a convenient notation for specifying the characters which
+are in the class by enumerating those that are not. It is not an assertion: it
+still consumes a character from the subject string, and fails if the current
+pointer is at the end of the string.
+
+The newline character is never treated in any special way in character classes,
+whatever the setting of the PCRE_DOTALL or PCRE_MULTILINE options is. A class
+such as [^a] will always match a newline.
+
+The minus (hyphen) character can be used to specify a range of characters in a
+character class. For example, [d-m] matches any letter between d and m,
+inclusive. If a minus character is required in a class, it must be escaped with
+\\ or appear in a position where it cannot be interpreted as indicating a
+range, typically as the first or last character in the class. It is not
+possible to have the character "]" as the end character of a range, since a
+sequence such as [w-] is interpreted as a class of two characters. The octal or
+hexadecimal representation of "]" can, however, be used to end a range.
+
+Ranges operate in ASCII collating sequence. They can also be used for
+characters specified numerically, for example [\\000-\\037]. If a range such as
+[W-c] is used when PCRE_CASELESS is set, it matches the letters involved in
+either case.
+
+The character types \\d, \\D, \\s, \\S, \\w, and \\W may also appear in a
+character class, and add the characters that they match to the class. For
+example, the class [^\\W_] matches any letter or digit.
+
+All non-alphameric characters other than \\, -, ^ (at the start) and the
+terminating ] are non-special in character classes, but it does no harm if they
+are escaped.
+
+
+.SH VERTICAL BAR
+Vertical bar characters are used to separate alternative patterns. The matching
+process tries all the alternatives in turn. For example, the pattern
+
+  gilbert|sullivan
+
+matches either "gilbert" or "sullivan". Any number of alternatives can be used,
+and an empty alternative is permitted (matching the empty string).
+
+
+.SH SUBPATTERNS
+Subpatterns are delimited by parentheses (round brackets), which can be nested.
+Marking part of a pattern as a subpattern does two things:
+
+1. It localizes a set of alternatives. For example, the pattern
+
+  cat(aract|erpillar|)
+
+matches one of the words "cat", "cataract", or "caterpillar". Without the
+parentheses, it would match "cataract", "erpillar" or the empty string.
+
+2. It sets up the subpattern as a capturing subpattern (as defined above).
+When the whole pattern matches, that portion of the subject string that matched
+the subpattern is passed back to the caller via the \fIovector\fR argument of
+\fBpcre_exec()\fR. Opening parentheses are counted from left to right (starting
+from 1) to obtain the numbers of the capturing subpatterns.
+
+For example, if the string "the red king" is matched against the pattern
+
+  the ((red|white) (king|queen))
+
+the captured substrings are "red king", "red", and "king", and are numbered 1,
+2, and 3.
+
+The fact that plain parentheses fulfil two functions is not always helpful.
+There are often times when a grouping subpattern is required without a
+capturing requirement. If an opening parenthesis is followed by "?:", the
+subpattern does not do any capturing, and is not counted when computing the
+number of any subsequent capturing subpatterns. For example, if the string "the
+white queen" is matched against the pattern
+
+  the ((?:red|white) (king|queen))
+
+the captured substrings are "white queen" and "queen", and are numbered 1 and
+2. The maximum number of captured substrings is 99, and the maximum number of
+all subpatterns, both capturing and non-capturing, is 200.
+
+
+.SH BACK REFERENCES
+Outside a character class, a backslash followed by a digit greater than 0 (and
+possibly further digits) is a back reference to a capturing subpattern earlier
+(i.e. to its left) in the pattern, provided there have been that many previous
+capturing left parentheses. However, if the decimal number following the
+backslash is less than 10, it is always taken as a back reference, and causes
+an error if there have not been that many previous capturing left parentheses.
+See the section entitled "Backslash" above for further details of the handling
+of digits following a backslash.
+
+A back reference matches whatever actually matched the capturing subpattern in
+the current subject string, rather than anything matching the subpattern
+itself. So the pattern
+
+   (sens|respons)e and \\1ibility
+
+matches "sense and sensibility" and "response and responsibility", but not
+"sense and responsibility".
+
+There may be more than one back reference to the same subpattern. If a
+subpattern has not actually been used in a particular match, then any back
+references to it always fail. For example, the pattern
+
+  (a|(bc))\\2
+
+always fails if it starts to match "a" rather than "bc". Because there may be
+up to 99 back references, all digits following the backslash are taken
+as part of a potential back reference number. If the pattern continues with a
+digit character, then some delimiter must be used to terminate the back
+reference. If the PCRE_EXTENDED option is set, this can be whitespace.
+Otherwise an empty comment can be used.
+
+
+.SH REPETITION
+Repetition is specified by quantifiers, which can follow any of the following
+items:
+
+  a single character, possibly escaped
+  the . metacharacter
+  a character class
+  a back reference
+  a parenthesized subpattern
+
+The general repetition quantifier specifies a minimum and maximum number of
+permitted matches, by giving the two numbers in curly brackets (braces),
+separated by a comma. The numbers must be less than 65536, and the first must
+be less than or equal to the second. For example:
+
+  z{2,4}
+
+matches "zz", "zzz", or "zzzz". A closing brace on its own is not a special
+character. If the second number is omitted, but the comma is present, there is
+no upper limit; if the second number and the comma are both omitted, the
+quantifier specifies an exact number of required matches. Thus
+
+  [aeiou]{3,}
+
+matches at least 3 successive vowels, but may match many more, while
+
+  \\d{8}
+
+matches exactly 8 digits. An opening curly bracket that appears in a position
+where a quantifier is not allowed, or one that does not match the syntax of a
+quantifier, is taken as a literal character. For example, "{,6}" is not a
+quantifier, but a literal string of four characters.
+
+The quantifier {0} is permitted, causing the expression to behave as if the
+previous item and the quantifier were not present.
+
+For convenience (and historical compatibility) the three most common
+quantifiers have single-character abbreviations:
+
+  *    is equivalent to {0,}
+  +    is equivalent to {1,}
+  ?    is equivalent to {0,1}
+
+By default, the quantifiers are "greedy", that is, they match as much as
+possible (up to the maximum number of permitted times), without causing the
+rest of the pattern to fail. The classic example of where this gives problems
+is in trying to match comments in C programs. These appear between the
+sequences /* and */ and within the sequence, individual * and / characters may
+appear. An attempt to match C comments by applying the pattern
+
+  /\\*.*\\*/
+
+to the string
+
+  /* first command */  not comment  /* second comment */
+
+fails, because it matches the entire string due to the greediness of the .*
+item.
+
+However, if a quantifier is followed by a question mark, then it ceases to be
+greedy, and instead matches the minimum number of times possible, so the
+pattern
+
+  /\\*.*?\\*/
+
+does the right thing with the C comments. The meaning of the various
+quantifiers is not otherwise changed, just the preferred number of matches.
+Do not confuse this use of question mark with its use as a quantifier in its
+own right. Because it has two uses, it can sometimes appear doubled, as in
+
+   \\d??\\d
+
+which matches one digit by preference, but can match two if that is the only
+way the rest of the pattern matches.
+
+When a parenthesized subpattern is quantified a with minimum repeat count that
+is greater than 1 or with a limited maximum, more store is required for the
+compiled pattern, in proportion to the size of the minimum or maximum.
+
+If a pattern starts with .* then it is implicitly anchored, since whatever
+follows will be tried against every character position in the subject string.
+PCRE treats this as though it were preceded by \\A.
+
+When a capturing subpattern is repeated, the value captured is the substring
+that matched the final iteration. For example,
+
+   (\s*tweedle[dume]{3})+\\1
+
+matches "tweedledum tweedledee tweedledee" but not "tweedledum tweedledee
+tweedledum".
+
+
+.SH ASSERTIONS
+An assertion is a test on the characters following the current matching point
+that does not actually consume any of those characters. The simple assertions
+coded as \\b, \\B, \\A, \\Z, ^ and $ are described above. More complicated
+assertions are coded as subpatterns starting with (?= for positive assertions,
+and (?! for negative assertions. For example,
+
+  \\w+(?=;)
+
+matches a word followed by a semicolon, but does not include the semicolon in
+the match, and
+
+  foo(?!bar)
+
+matches any occurrence of "foo" that is not followed by "bar". Note that the
+apparently similar pattern
+
+  (?!foo)bar
+
+does not find an occurrence of "bar" that is preceded by something other than
+"foo"; it finds any occurrence of "bar" whatsoever, because the assertion
+(?!foo) is always true when the next three characters are "bar".
+
+Assertion subpatterns are not capturing subpatterns, and may not be repeated,
+because it makes no sense to assert the same thing several times. If an
+assertion contains capturing subpatterns within it, these are always counted
+for the purposes of numbering the capturing subpatterns in the whole pattern.
+Substring capturing is carried out for positive assertions, but it does not
+make sense for negative assertions.
+
+Assertions count towards the maximum of 200 parenthesized subpatterns.
+
+
+.SH ONCE-ONLY SUBPATTERNS
+The facility described in this section is available only when the PCRE_EXTRA
+option is set at compile time. It is an extension to Perl regular expressions.
+
+With both maximizing and minimizing repetition, failure of what follows
+normally causes the repeated item to be re-evaluated to see if a different
+number of repeats allows the rest of the pattern to match. Sometimes it is
+useful to prevent this, either to change the nature of the match, or to cause
+it fail earlier than it otherwise might when the author or the pattern knows
+there is no point in carrying on.
+
+Consider, for example, the pattern \\d+foo when applied to the subject line
+
+   123456bar
+
+After matching all 6 digits and then failing to match "foo", the normal
+action of the matcher is to try again with only 5 digits matching the \\d+
+item, and then with 4, and so on, before ultimately failing. Once-only
+subpatterns provide the means for specifying that once a portion of the pattern
+has matched, it is not to be re-evaluated in this way, so the matcher would
+give up immediately on failing to match "foo" the first time. The notation is
+another kind of special parenthesis, starting with (?> as in this example:
+
+  (?>\d+)bar
+
+This kind of parenthesis "locks up" the  part of the pattern it contains once
+it has matched, and a failure further into the pattern is prevented from
+backtracking into it. Backtracking past it to previous items, however, works as
+normal.
+
+For simple cases such as the above example, this feature can be though of as a
+maximizing repeat that must swallow everything it can. So, while both \\d+ and
+\\d+? are prepared to adjust the number of digits they match in order to make
+the rest of the pattern match, (?>\\d+) can only match an entire sequence of
+digits.
+
+This construction can of course contain arbitrarily complicated subpatterns,
+and it can be nested. Contrast with the \\X assertion, which is a Prolog-like
+"cut".
+
+
+.SH COMMENTS
+The sequence (?# marks the start of a comment which continues up to the next
+closing parenthesis. Nested parentheses are not permitted. The characters
+that make up a comment play no part in the pattern matching at all.
+
+If the PCRE_EXTENDED option is set, an unescaped # character outside a
+character class introduces a comment that continues up to the next newline
+character in the pattern.
+
+
+.SH INTERNAL FLAG SETTING
+If the sequence (?i) occurs anywhere in a pattern, it has the effect of setting
+the PCRE_CASELESS option, that is, all letters are matched in a
+case-independent manner. The option applies to the whole pattern, not just to
+the portion that follows it.
+
+If the sequence (?m) occurs anywhere in a pattern, it has the effect of setting
+the PCRE_MULTILINE option, that is, subject strings matched by this pattern are
+treated as consisting of multiple lines.
+
+If the sequence (?s) occurs anywhere in a pattern, it has the effect of setting
+the PCRE_DOTALL option, so that dot metacharacters match newlines as well as
+all other characters.
+
+If the sequence (?x) occurs anywhere in a pattern, it has the effect of setting
+the PCRE_EXTENDED option, that is, whitespace is ignored and # introduces a
+comment that lasts till the next newline. The option applies to the whole
+pattern, not just to the portion that follows it.
+
+If more than one option is required, they can be specified jointly, for example
+as (?ix) or (?mi).
+
+
+.SH PERFORMANCE
+Certain items that may appear in patterns are more efficient than others. It is
+more efficient to use a character class like [aeiou] than a set of alternatives
+such as (a|e|i|o|u). In general, the simplest construction that provides the
+required behaviour is usually the most efficient. Jeffrey Friedl's book
+contains a lot of discussion about optimizing regular expressions for efficient
+performance.
+
+The use of PCRE_MULTILINE causes additional processing and should be avoided
+when it is not necessary. Caseless matching of character classes is more
+efficient if PCRE_CASELESS is set when the pattern is compiled.
+
+
+.SH AUTHOR
+Philip Hazel <ph10@cam.ac.uk>
+.br
+University Computing Service,
+.br
+New Museums Site,
+.br
+Cambridge CB2 3QG, England.
+.br
+Phone: +44 1223 334714
+
+Copyright (c) 1997 University of Cambridge.
diff --git a/pcre.c b/pcre.c
new file mode 100644
index 0000000..4877095
--- /dev/null
+++ b/pcre.c
@@ -0,0 +1,3510 @@
+/*************************************************
+*      Perl-Compatible Regular Expressions       *
+*************************************************/
+
+/*
+This is a library of functions to support regular expressions whose syntax
+and semantics are as close as possible to those of the Perl 5 language. See
+the file Tech.Notes for some information on the internals.
+
+Written by: Philip Hazel <ph10@cam.ac.uk>
+
+           Copyright (c) 1997 University of Cambridge
+
+-----------------------------------------------------------------------------
+Permission is granted to anyone to use this software for any purpose on any
+computer system, and to redistribute it freely, subject to the following
+restrictions:
+
+1. This software is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+
+2. The origin of this software must not be misrepresented, either by
+   explicit claim or by omission.
+
+3. Altered versions must be plainly marked as such, and must not be
+   misrepresented as being the original software.
+-----------------------------------------------------------------------------
+*/
+
+
+/* Define DEBUG to get debugging output on stdout. */
+
+/* #define DEBUG */
+
+
+/* Include the internals header, which itself includes Standard C headers plus
+the external pcre header. */
+
+#include "internal.h"
+
+
+/* Min and max values for the common repeats; for the maxima, 0 => infinity */
+
+static char rep_min[] = { 0, 0, 1, 1, 0, 0 };
+static char rep_max[] = { 0, 0, 0, 0, 1, 1 };
+
+/* Text forms of OP_ values and things, for debugging */
+
+#ifdef DEBUG
+static char *OP_names[] = { "End", "\\A", "\\B", "\\b", "\\D", "\\d",
+  "\\S", "\\s", "\\W", "\\w", "Cut", "\\Z", "^", "$", "Any", "chars",
+  "not",
+  "*", "*?", "+", "+?", "?", "??", "{", "{", "{",
+  "*", "*?", "+", "+?", "?", "??", "{", "{", "{",
+  "*", "*?", "+", "+?", "?", "??", "{", "{", "{",
+  "*", "*?", "+", "+?", "?", "??", "{", "{",
+  "class", "Ref",
+  "Alt", "Ket", "KetRmax", "KetRmin", "Assert", "Assert not", "Once",
+  "Brazero", "Braminzero", "Bra"
+};
+#endif
+
+/* Table for handling escaped characters in the range '0'-'z'. Positive returns
+are simple data values; negative values are for special things like \d and so
+on. Zero means further processing is needed (for things like \x), or the escape
+is invalid. */
+
+static short int escapes[] = {
+    0,      0,      0,      0,      0,      0,      0,      0,   /* 0 - 7 */
+    0,      0,    ':',    ';',    '<',    '=',    '>',    '?',   /* 8 - ? */
+  '@', -ESC_A, -ESC_B,      0, -ESC_D,      0,      0,      0,   /* @ - G */
+    0,      0,      0,      0,      0,      0,      0,      0,   /* H - O */
+    0,      0,      0, -ESC_S,      0,      0,      0, -ESC_W,   /* P - W */
+    0,      0, -ESC_Z,    '[',   '\\',    ']',    '^',    '_',   /* X - _ */
+  '`',      7, -ESC_b,      0, -ESC_d,     27,   '\f',      0,   /* ` - g */
+    0,      0,      0,      0,      0,      0,   '\n',      0,   /* h - o */
+    0,      0,   '\r', -ESC_s,   '\t',      0,      0, -ESC_w,   /* p - w */
+    0,      0,      0                                            /* x - z */
+};
+
+/* Definition to allow mutual recursion */
+
+static BOOL compile_regex(int, int *,uschar **,uschar **,char **);
+
+/* Structure for passing "static" information around between the functions
+doing the matching, so that they are thread-safe. */
+
+typedef struct match_data {
+  int    errorcode;             /* As it says */
+  int   *offset_vector;         /* Offset vector */
+  int    offset_end;            /* One past the end */
+  BOOL   offset_overflow;       /* Set if too many extractions */
+  BOOL   caseless;              /* Case-independent flag */
+  BOOL   runtime_caseless;      /* Caseless forced at run time */
+  BOOL   multiline;             /* Multiline flag */
+  BOOL   notbol;                /* NOTBOL flag */
+  BOOL   noteol;                /* NOTEOL flag */
+  BOOL   dotall;                /* Dot matches any char */
+  BOOL   endonly;               /* Dollar not before final \n */
+  uschar *start_subject;        /* Start of the subject string */
+  uschar *end_subject;          /* End of the subject string */
+  jmp_buf fail_env;             /* Environment for longjump() break out */
+  uschar *end_match_ptr;        /* Subject position at end match */
+  int     end_offset_top;       /* Highwater mark at end of match */
+} match_data;
+
+
+
+/*************************************************
+*               Global variables                 *
+*************************************************/
+
+/* PCRE is thread-clean and doesn't use any global variables in the normal
+sense. However, it calls memory allocation and free functions via the two
+indirections below, which are can be changed by the caller, but are shared
+between all threads. */
+
+void *(*pcre_malloc)(size_t) = malloc;
+void  (*pcre_free)(void *) = free;
+
+
+
+
+/*************************************************
+*          Return version string                 *
+*************************************************/
+
+char *
+pcre_version(void)
+{
+return PCRE_VERSION;
+}
+
+
+
+
+/*************************************************
+*       Return info about a compiled pattern     *
+*************************************************/
+
+/* This function picks potentially useful data out of the private
+structure.
+
+Arguments:
+  external_re   points to compiled code
+  optptr        where to pass back the options
+  first_char    where to pass back the first character,
+                or -1 if multiline and all branches start ^,
+                or -2 otherwise
+
+Returns:        number of identifying extraction brackets
+                or negative values on error
+*/
+
+int
+pcre_info(const pcre *external_re, int *optptr, int *first_char)
+{
+real_pcre *re = (real_pcre *)external_re;
+if (re == NULL) return PCRE_ERROR_NULL;
+if (re->magic_number != MAGIC_NUMBER) return PCRE_ERROR_BADMAGIC;
+if (optptr != NULL) *optptr = (re->options & PUBLIC_OPTIONS);
+if (first_char != NULL)
+  *first_char = ((re->options & PCRE_FIRSTSET) != 0)? re->first_char :
+     ((re->options & PCRE_STARTLINE) != 0)? -1 : -2;
+return re->top_bracket;
+}
+
+
+
+
+#ifdef DEBUG
+/*************************************************
+*        Debugging function to print chars       *
+*************************************************/
+
+/* Print a sequence of chars in printable format, stopping at the end of the
+subject if the requested.
+
+Arguments:
+  p           points to characters
+  length      number to print
+  is_subject  TRUE if printing from within md->start_subject
+  md          pointer to matching data block, if is_subject is TRUE
+
+Returns:     nothing
+*/
+
+static pchars(uschar *p, int length, BOOL is_subject, match_data *md)
+{
+int c;
+if (is_subject && length > md->end_subject - p) length = md->end_subject - p;
+while (length-- > 0)
+  if (isprint(c = *(p++))) printf("%c", c); else printf("\\x%02x", c);
+}
+#endif
+
+
+
+
+/*************************************************
+*         Check subpattern for empty operand     *
+*************************************************/
+
+/* This function checks a bracketed subpattern to see if any of the paths
+through it could match an empty string. This is used to diagnose an error if
+such a subpattern is followed by a quantifier with an unlimited upper bound.
+
+Argument:
+  code      points to the opening bracket
+
+Returns:    TRUE or FALSE
+*/
+
+static BOOL
+could_be_empty(uschar *code)
+{
+do {
+  uschar *cc = code + 3;
+
+  /* Scan along the opcodes for this branch; as soon as we find something
+  that matches a non-empty string, break out and advance to test the next
+  branch. If we get to the end of the branch, return TRUE for the whole
+  sub-expression. */
+
+  for (;;)
+    {
+    /* Test an embedded subpattern; if it could not be empty, break the
+    loop. Otherwise carry on in the branch. */
+
+    if ((int)(*cc) >= OP_BRA)
+      {
+      if (!could_be_empty(cc)) break;
+      do cc += (cc[1] << 8) + cc[2]; while (*cc == OP_ALT);
+      cc += 3;
+      }
+
+    else switch (*cc)
+      {
+      /* Reached end of a branch: the subpattern may match the empty string */
+
+      case OP_ALT:
+      case OP_KET:
+      case OP_KETRMAX:
+      case OP_KETRMIN:
+      return TRUE;
+
+      /* Skip over assertive subpatterns */
+
+      case OP_ASSERT:
+      case OP_ASSERT_NOT:
+      do cc += (cc[1] << 8) + cc[2]; while (*cc == OP_ALT);
+      cc += 3;
+      break;
+
+      /* Skip over things that don't match chars */
+
+      case OP_SOD:
+      case OP_EOD:
+      case OP_CIRC:
+      case OP_DOLL:
+      case OP_BRAZERO:
+      case OP_BRAMINZERO:
+      case OP_NOT_WORD_BOUNDARY:
+      case OP_WORD_BOUNDARY:
+      cc++;
+      break;
+
+      /* Skip over simple repeats with zero lower bound */
+
+      case OP_STAR:
+      case OP_MINSTAR:
+      case OP_QUERY:
+      case OP_MINQUERY:
+      case OP_TYPESTAR:
+      case OP_TYPEMINSTAR:
+      case OP_TYPEQUERY:
+      case OP_TYPEMINQUERY:
+      cc += 2;
+      break;
+
+      /* Skip over UPTOs (lower bound is zero) */
+
+      case OP_UPTO:
+      case OP_MINUPTO:
+      case OP_TYPEUPTO:
+      case OP_TYPEMINUPTO:
+      cc += 4;
+      break;
+
+      /* Check a class or a back reference for a zero minimum */
+
+      case OP_CLASS:
+      case OP_REF:
+      cc += (*cc == OP_REF)? 2 : 4 + 2 * cc[2] + cc[3];
+
+      switch (*cc)
+        {
+        case OP_CRSTAR:
+        case OP_CRMINSTAR:
+        case OP_CRQUERY:
+        case OP_CRMINQUERY:
+        cc++;
+        break;
+
+        case OP_CRRANGE:
+        case OP_CRMINRANGE:
+        if ((cc[1] << 8) + cc[2] != 0) goto NEXT_BRANCH;
+        cc += 3;
+        break;
+
+        default:
+        goto NEXT_BRANCH;
+        }
+      break;
+
+      /* Anything else matches at least one character */
+
+      default:
+      goto NEXT_BRANCH;
+      }
+    }
+
+  NEXT_BRANCH:
+  code += (code[1] << 8) + code[2];
+  }
+while (*code == OP_ALT);
+
+/* No branches match the empty string */
+
+return FALSE;
+}
+
+
+
+/*************************************************
+*            Handle escapes                      *
+*************************************************/
+
+/* This function is called when a \ has been encountered. It either returns a
+positive value for a simple escape such as \n, or a negative value which
+encodes one of the more complicated things such as \d. On entry, ptr is
+pointing at the \. On exit, it is on the final character of the escape
+sequence.
+
+Arguments:
+  ptrptr     points to the pattern position pointer
+  errorptr   points to the pointer to the error message
+  bracount   number of previous extracting brackets
+  options    the options bits
+  isclass    TRUE if inside a character class
+
+Returns:     zero or positive => a data character
+             negative => a special escape sequence
+             on error, errorptr is set
+*/
+
+static int
+check_escape(uschar **ptrptr, char **errorptr, int bracount, int options,
+  BOOL isclass)
+{
+uschar *ptr = *ptrptr;
+int c = *(++ptr) & 255;   /* Ensure > 0 on signed-char systems */
+int i;
+
+if (c == 0) *errorptr = ERR1;
+
+/* Digits or letters may have special meaning; all others are literals. */
+
+else if (c < '0' || c > 'z') {}
+
+/* Do an initial lookup in a table. A non-zero result is something that can be
+returned immediately. Otherwise further processing may be required. */
+
+else if ((i = escapes[c - '0']) != 0) c = i;
+
+/* Escapes that need further processing, or are illegal. */
+
+else
+  {
+  uschar *oldptr;
+  switch (c)
+    {
+    /* The handling of escape sequences consisting of a string of digits
+    starting with one that is not zero is not straightforward. By experiment,
+    the way Perl works seems to be as follows:
+
+    Outside a character class, the digits are read as a decimal number. If the
+    number is less than 10, or if there are that many previous extracting
+    left brackets, then it is a back reference. Otherwise, up to three octal
+    digits are read to form an escaped byte. Thus \123 is likely to be octal
+    123 (cf \0123, which is octal 012 followed by the literal 3). If the octal
+    value is greater than 377, the least significant 8 bits are taken. Inside a
+    character class, \ followed by a digit is always an octal number. */
+
+    case '1': case '2': case '3': case '4': case '5':
+    case '6': case '7': case '8': case '9':
+
+    if (!isclass)
+      {
+      oldptr = ptr;
+      c -= '0';
+      while ((pcre_ctypes[ptr[1]] & ctype_digit) != 0)
+        c = c * 10 + *(++ptr) - '0';
+      if (c < 10 || c <= bracount)
+        {
+        c = -(ESC_REF + c);
+        break;
+        }
+      ptr = oldptr;      /* Put the pointer back and fall through */
+      }
+
+    /* Handle an octal number following \. If the first digit is 8 or 9, Perl
+    generates a binary zero byte and treats the digit as a following literal.
+    Thus we have to pull back the pointer by one. */
+
+    if ((c = *ptr) >= '8')
+      {
+      ptr--;
+      c = 0;
+      break;
+      }
+
+    /* \0 always starts an octal number, but we may drop through to here with a
+    larger first octal digit */
+
+    case '0':
+    c -= '0';
+    while(i++ < 2 && (pcre_ctypes[ptr[1]] & ctype_digit) != 0 &&
+      ptr[1] != '8' && ptr[1] != '9')
+        c = c * 8 + *(++ptr) - '0';
+    break;
+
+    /* Special escapes not starting with a digit are straightforward */
+
+    case 'x':
+    c = 0;
+    while (i++ < 2 && (pcre_ctypes[ptr[1]] & ctype_xdigit) != 0)
+      {
+      ptr++;
+      c = c * 16 + pcre_lcc[*ptr] -
+        (((pcre_ctypes[*ptr] & ctype_digit) != 0)? '0' : 'W');
+      }
+    break;
+
+    case 'c':
+    c = *(++ptr);
+    if (c == 0)
+      {
+      *errorptr = ERR2;
+      return 0;
+      }
+
+    /* A letter is upper-cased; then the 0x40 bit is flipped */
+
+    if (c >= 'a' && c <= 'z') c = pcre_fcc[c];
+    c ^= 0x40;
+    break;
+
+    /* PCRE_EXTRA enables extensions to Perl in the matter of escapes. Any
+    other alphameric following \ is an error if PCRE_EXTRA was set; otherwise,
+    for Perl compatibility, it is a literal. */
+
+    default:
+    if ((options & PCRE_EXTRA) != 0) switch(c)
+      {
+      case 'X':
+      c = -ESC_X;      /* This could be a lookup if it ever got into Perl */
+      break;
+
+      default:
+      *errorptr = ERR3;
+      break;
+      }
+    break;
+    }
+  }
+
+*ptrptr = ptr;
+return c;
+}
+
+
+
+/*************************************************
+*            Check for counted repeat            *
+*************************************************/
+
+/* This function is called when a '{' is encountered in a place where it might
+start a quantifier. It looks ahead to see if it really is a quantifier or not.
+It is only a quantifier if it is one of the forms {ddd} {ddd,} or {ddd,ddd}
+where the ddds are digits.
+
+Arguments:
+  p         pointer to the first char after '{'
+
+Returns:    TRUE or FALSE
+*/
+
+static BOOL
+is_counted_repeat(uschar *p)
+{
+if ((pcre_ctypes[*p++] & ctype_digit) == 0) return FALSE;
+while ((pcre_ctypes[*p] & ctype_digit) != 0) p++;
+if (*p == '}') return TRUE;
+
+if (*p++ != ',') return FALSE;
+if (*p == '}') return TRUE;
+
+if ((pcre_ctypes[*p++] & ctype_digit) == 0) return FALSE;
+while ((pcre_ctypes[*p] & ctype_digit) != 0) p++;
+return (*p == '}');
+}
+
+
+
+/*************************************************
+*         Read repeat counts                     *
+*************************************************/
+
+/* Read an item of the form {n,m} and return the values. This is called only
+after is_counted_repeat() has confirmed that a repeat-count quantifier exists,
+so the syntax is guaranteed to be correct, but we need to check the values.
+
+Arguments:
+  p          pointer to first char after '{'
+  minp       pointer to int for min
+  maxp       pointer to int for max
+             returned as -1 if no max
+  errorptr   points to pointer to error message
+
+Returns:     pointer to '}' on success;
+             current ptr on error, with errorptr set
+*/
+
+static uschar *
+read_repeat_counts(uschar *p, int *minp, int *maxp, char **errorptr)
+{
+int min = 0;
+int max = -1;
+
+while ((pcre_ctypes[*p] & ctype_digit) != 0) min = min * 10 + *p++ - '0';
+
+if (*p == '}') max = min; else
+  {
+  if (*(++p) != '}')
+    {
+    max = 0;
+    while((pcre_ctypes[*p] & ctype_digit) != 0) max = max * 10 + *p++ - '0';
+    if (max < min)
+      {
+      *errorptr = ERR4;
+      return p;
+      }
+    }
+  }
+
+/* Do paranoid checks, then fill in the required variables, and pass back the
+pointer to the terminating '}'. */
+
+if (min > 65535 || max > 65535)
+  *errorptr = ERR5;
+else
+  {
+  *minp = min;
+  *maxp = max;
+  }
+return p;
+}
+
+
+
+/*************************************************
+*           Compile one branch                   *
+*************************************************/
+
+/* Scan the pattern, compiling it into the code vector.
+
+Arguments:
+  options    the option bits
+  bracket    points to number of brackets used
+  code       points to the pointer to the current code point
+  ptrptr     points to the current pattern pointer
+  errorptr   points to pointer to error message
+
+Returns:     TRUE on success
+             FALSE, with *errorptr set on error
+*/
+
+static BOOL
+compile_branch(int options, int *brackets, uschar **codeptr, uschar **ptrptr,
+  char **errorptr)
+{
+int repeat_type, op_type;
+int repeat_min, repeat_max;
+int bravalue, length;
+register int c;
+register uschar *code = *codeptr;
+uschar *ptr = *ptrptr;
+uschar *previous = NULL;
+uschar *oldptr;
+uschar class[32];
+
+/* Switch on next character until the end of the branch */
+
+for (;; ptr++)
+  {
+  BOOL negate_class;
+  int  class_charcount;
+  int  class_lastchar;
+
+  c = *ptr;
+  if ((options & PCRE_EXTENDED) != 0)
+    {
+    if ((pcre_ctypes[c] & ctype_space) != 0) continue;
+    if (c == '#')
+      {
+      while ((c = *(++ptr)) != 0 && c != '\n');
+      continue;
+      }
+    }
+
+  switch(c)
+    {
+    /* The branch terminates at end of string, |, or ). */
+
+    case 0:
+    case '|':
+    case ')':
+    *codeptr = code;
+    *ptrptr = ptr;
+    return TRUE;
+
+    /* Handle single-character metacharacters */
+
+    case '^':
+    previous = NULL;
+    *code++ = OP_CIRC;
+    break;
+
+    case '$':
+    previous = NULL;
+    *code++ = OP_DOLL;
+    break;
+
+    case '.':
+    previous = code;
+    *code++ = OP_ANY;
+    break;
+
+    /* Character classes. These always build a 32-byte bitmap of the permitted
+    characters, except in the special case where there is only one character.
+    For negated classes, we build the map as usual, then invert it at the end.
+    */
+
+    case '[':
+    previous = code;
+    *code++ = OP_CLASS;
+
+    /* If the first character is '^', set the negation flag */
+
+    if ((c = *(++ptr)) == '^')
+      {
+      negate_class = TRUE;
+      c = *(++ptr);
+      }
+    else negate_class = FALSE;
+
+    /* Keep a count of chars so that we can optimize the case of just a single
+    character. */
+
+    class_charcount = 0;
+    class_lastchar = -1;
+
+    /* Initialize the 32-char bit map to all zeros. We have to build the
+    map in a temporary bit of store, in case the class contains only 1
+    character, because in that case the compiled code doesn't use the
+    bit map. */
+
+    memset(class, 0, 32 * sizeof(uschar));
+
+    /* Process characters until ] is reached. By writing this as a "do" it
+    means that an initial ] is taken as a data character. */
+
+    do
+      {
+      if (c == 0)
+        {
+        *errorptr = ERR6;
+        goto FAILED;
+        }
+
+      /* Backslash may introduce a single character, or it may introduce one
+      of the specials, which just set a flag. Escaped items are checked for
+      validity in the pre-compiling pass. The sequence \b is a special case.
+      Inside a class (and only there) it is treated as backslash. Elsewhere
+      it marks a word boundary. Other escapes have preset maps ready to
+      or into the one we are building. We assume they have more than one
+      character in them, so set class_count bigger than one. */
+
+      if (c == '\\')
+        {
+        c = check_escape(&ptr, errorptr, *brackets, options, TRUE);
+        if (-c == ESC_b) c = '\b';
+        else if (c < 0)
+          {
+          class_charcount = 10;
+          switch (-c)
+            {
+            case ESC_d:
+            for (c = 0; c < 32; c++) class[c] |= pcre_cbits[c+cbit_digit];
+            continue;
+
+            case ESC_D:
+            for (c = 0; c < 32; c++) class[c] |= ~pcre_cbits[c+cbit_digit];
+            continue;
+
+            case ESC_w:
+            for (c = 0; c < 32; c++)
+              class[c] |= (pcre_cbits[c] | pcre_cbits[c+cbit_word]);
+            continue;
+
+            case ESC_W:
+            for (c = 0; c < 32; c++)
+              class[c] |= ~(pcre_cbits[c] | pcre_cbits[c+cbit_word]);
+            continue;
+
+            case ESC_s:
+            for (c = 0; c < 32; c++) class[c] |= pcre_cbits[c+cbit_space];
+            continue;
+
+            case ESC_S:
+            for (c = 0; c < 32; c++) class[c] |= ~pcre_cbits[c+cbit_space];
+            continue;
+
+            default:
+            *errorptr = ERR7;
+            goto FAILED;
+            }
+          }
+        /* Fall through if single character */
+        }
+
+      /* A single character may be followed by '-' to form a range. However,
+      Perl does not permit ']' to be the end of the range. A '-' character
+      here is treated as a literal. */
+
+      if (ptr[1] == '-' && ptr[2] != ']')
+        {
+        int d;
+        ptr += 2;
+        d = *ptr;
+
+        if (d == 0)
+          {
+          *errorptr = ERR6;
+          goto FAILED;
+          }
+
+        /* The second part of a range can be a single-character escape, but
+        not any of the other escapes. */
+
+        if (d == '\\')
+          {
+          d = check_escape(&ptr, errorptr, *brackets, options, TRUE);
+          if (d < 0)
+            {
+            if (d == -ESC_b) d = '\b'; else
+              {
+              *errorptr = ERR7;
+              goto FAILED;
+              }
+            }
+          }
+
+        if (d < c)
+          {
+          *errorptr = ERR8;
+          goto FAILED;
+          }
+
+        for (; c <= d; c++)
+          {
+          class[c/8] |= (1 << (c&7));
+          if ((options & PCRE_CASELESS) != 0)
+            {
+            int uc = pcre_fcc[c];           /* flip case */
+            class[uc/8] |= (1 << (uc&7));
+            }
+          class_charcount++;                /* in case a one-char range */
+          class_lastchar = c;
+          }
+        continue;   /* Go get the next char in the class */
+        }
+
+      /* Handle a lone single character - we can get here for a normal
+      non-escape char, or after \ that introduces a single character. */
+
+      class [c/8] |= (1 << (c&7));
+      if ((options & PCRE_CASELESS) != 0)
+        {
+        c = pcre_fcc[c];   /* flip case */
+        class[c/8] |= (1 << (c&7));
+        }
+      class_charcount++;
+      class_lastchar = c;
+      }
+
+    /* Loop until ']' reached; the check for end of string happens inside the
+    loop. This "while" is the end of the "do" above. */
+
+    while ((c = *(++ptr)) != ']');
+
+    /* If class_charcount is 1 and class_lastchar is not negative, we saw
+    precisely one character. This doesn't need the whole 32-byte bit map.
+    We turn it into a 1-character OP_CHAR if it's positive, or OP_NOT if
+    it's negative. */
+
+    if (class_charcount == 1 && class_lastchar >= 0)
+      {
+      if (negate_class)
+        {
+        code[-1] = OP_NOT;
+        }
+      else
+        {
+        code[-1] = OP_CHARS;
+        *code++ = 1;
+        }
+      *code++ = class_lastchar;
+      }
+
+    /* Otherwise, negate the 32-byte map if necessary, and copy it into
+    the code vector. */
+
+    else
+      {
+      if (negate_class)
+        for (c = 0; c < 32; c++) code[c] = ~class[c];
+      else
+        memcpy(code, class, 32);
+      code += 32;
+      }
+    break;
+
+    /* Various kinds of repeat */
+
+    case '{':
+    if (!is_counted_repeat(ptr+1)) goto NORMAL_CHAR;
+    ptr = read_repeat_counts(ptr+1, &repeat_min, &repeat_max, errorptr);
+    if (*errorptr != NULL) goto FAILED;
+    goto REPEAT;
+
+    case '*':
+    repeat_min = 0;
+    repeat_max = -1;
+    goto REPEAT;
+
+    case '+':
+    repeat_min = 1;
+    repeat_max = -1;
+    goto REPEAT;
+
+    case '?':
+    repeat_min = 0;
+    repeat_max = 1;
+
+    REPEAT:
+    if (previous == NULL)
+      {
+      *errorptr = ERR9;
+      goto FAILED;
+      }
+
+    /* If the next character is '?' this is a minimizing repeat. Advance to the
+    next character. */
+
+    if (ptr[1] == '?') { repeat_type = 1; ptr++; } else repeat_type = 0;
+
+    /* If the maximum is zero then the minimum must also be zero; Perl allows
+    this case, so we do too - by simply omitting the item altogether. */
+
+    if (repeat_max == 0) code = previous;
+
+    /* If previous was a string of characters, chop off the last one and use it
+    as the subject of the repeat. If there was only one character, we can
+    abolish the previous item altogether. */
+
+    else if (*previous == OP_CHARS)
+      {
+      int len = previous[1];
+      if (len == 1)
+        {
+        c = previous[2];
+        code = previous;
+        }
+      else
+        {
+        c = previous[len+1];
+        previous[1]--;
+        code--;
+        }
+      op_type = 0;                 /* Use single-char op codes */
+      goto OUTPUT_SINGLE_REPEAT;   /* Code shared with single character types */
+      }
+
+    /* If previous was a single negated character ([^a] or similar), we use
+    one of the special opcodes, replacing it. The code is shared with single-
+    character repeats by adding a suitable offset into repeat_type. */
+
+    else if ((int)*previous == OP_NOT)
+      {
+      op_type = OP_NOTSTAR - OP_STAR;  /* Use "not" opcodes */
+      c = previous[1];
+      code = previous;
+      goto OUTPUT_SINGLE_REPEAT;
+      }
+
+    /* If previous was a character type match (\d or similar), abolish it and
+    create a suitable repeat item. The code is shared with single-character
+    repeats by adding a suitable offset into repeat_type. */
+
+    else if ((int)*previous < OP_EOD || *previous == OP_ANY)
+      {
+      op_type = OP_TYPESTAR - OP_STAR;  /* Use type opcodes */
+      c = *previous;
+      code = previous;
+
+      OUTPUT_SINGLE_REPEAT:
+      repeat_type += op_type;      /* Combine both values for many cases */
+
+      /* A minimum of zero is handled either as the special case * or ?, or as
+      an UPTO, with the maximum given. */
+
+      if (repeat_min == 0)
+        {
+        if (repeat_max == -1) *code++ = OP_STAR + repeat_type;
+          else if (repeat_max == 1) *code++ = OP_QUERY + repeat_type;
+        else
+          {
+          *code++ = OP_UPTO + repeat_type;
+          *code++ = repeat_max >> 8;
+          *code++ = (repeat_max & 255);
+          }
+        }
+
+      /* The case {1,} is handled as the special case + */
+
+      else if (repeat_min == 1 && repeat_max == -1)
+        *code++ = OP_PLUS + repeat_type;
+
+      /* The case {n,n} is just an EXACT, while the general case {n,m} is
+      handled as an EXACT followed by an UPTO. An EXACT of 1 is optimized. */
+
+      else
+        {
+        if (repeat_min != 1)
+          {
+          *code++ = OP_EXACT + op_type;  /* NB EXACT doesn't have repeat_type */
+          *code++ = repeat_min >> 8;
+          *code++ = (repeat_min & 255);
+          }
+
+        /* If the mininum is 1 and the previous item was a character string,
+        we either have to put back the item that got cancelled if the string
+        length was 1, or add the character back onto the end of a longer
+        string. For a character type nothing need be done; it will just get put
+        back naturally. */
+
+        else if (*previous == OP_CHARS)
+          {
+          if (code == previous) code += 2; else previous[1]++;
+          }
+
+        /* Insert an UPTO if the max is greater than the min. */
+
+        if (repeat_max != repeat_min)
+          {
+          *code++ = c;
+          repeat_max -= repeat_min;
+          *code++ = OP_UPTO + repeat_type;
+          *code++ = repeat_max >> 8;
+          *code++ = (repeat_max & 255);
+          }
+        }
+
+      /* The character or character type itself comes last in all cases. */
+
+      *code++ = c;
+      }
+
+    /* If previous was a character class or a back reference, we put the repeat
+    stuff after it. */
+
+    else if (*previous == OP_CLASS || *previous == OP_REF)
+      {
+      if (repeat_min == 0 && repeat_max == -1)
+        *code++ = OP_CRSTAR + repeat_type;
+      else if (repeat_min == 1 && repeat_max == -1)
+        *code++ = OP_CRPLUS + repeat_type;
+      else if (repeat_min == 0 && repeat_max == 1)
+        *code++ = OP_CRQUERY + repeat_type;
+      else
+        {
+        *code++ = OP_CRRANGE + repeat_type;
+        *code++ = repeat_min >> 8;
+        *code++ = repeat_min & 255;
+        if (repeat_max == -1) repeat_max = 0;  /* 2-byte encoding for max */
+        *code++ = repeat_max >> 8;
+        *code++ = repeat_max & 255;
+        }
+      }
+
+    /* If previous was a bracket group, we may have to replicate it in certain
+    cases. If the maximum repeat count is unlimited, check that the bracket
+    group cannot match the empty string, and diagnose an error if it can. */
+
+    else if ((int)*previous >= OP_BRA)
+      {
+      int i;
+      int length = code - previous;
+
+      if (repeat_max == -1 && could_be_empty(previous))
+        {
+        *errorptr = ERR10;
+        goto FAILED;
+        }
+
+      /* If the minimum is greater than zero, and the maximum is unlimited or
+      equal to the minimum, the first copy remains where it is, and is
+      replicated up to the minimum number of times. This case includes the +
+      repeat, but of course no replication is needed in that case. */
+
+      if (repeat_min > 0 && (repeat_max == -1 || repeat_max == repeat_min))
+        {
+        for (i = 1; i < repeat_min; i++)
+          {
+          memcpy(code, previous, length);
+          code += length;
+          }
+        }
+
+      /* If the minimum is zero, stick BRAZERO in front of the first copy.
+      Then, if there is a fixed upper limit, replicated up to that many times,
+      sticking BRAZERO in front of all the optional ones. */
+
+      else
+        {
+        if (repeat_min == 0)
+          {
+          memmove(previous+1, previous, length);
+          code++;
+          *previous++ = OP_BRAZERO + repeat_type;
+          }
+
+        for (i = 1; i < repeat_min; i++)
+          {
+          memcpy(code, previous, length);
+          code += length;
+          }
+
+        for (i = (repeat_min > 0)? repeat_min : 1; i < repeat_max; i++)
+          {
+          *code++ = OP_BRAZERO + repeat_type;
+          memcpy(code, previous, length);
+          code += length;
+          }
+        }
+
+      /* If the maximum is unlimited, set a repeater in the final copy. */
+
+      if (repeat_max == -1) code[-3] = OP_KETRMAX + repeat_type;
+      }
+
+    /* Else there's some kind of shambles */
+
+    else
+      {
+      *errorptr = ERR11;
+      goto FAILED;
+      }
+
+    /* In all case we no longer have a previous item. */
+
+    previous = NULL;
+    break;
+
+
+    /* Start of nested bracket sub-expression, or comment or lookahead.
+    First deal with special things that can come after a bracket; all are
+    introduced by ?, and the appearance of any of them means that this is not a
+    referencing group. They were checked for validity in the first pass over
+    the string, so we don't have to check for syntax errors here.  */
+
+    case '(':
+    previous = code;              /* Only real brackets can be repeated */
+    if (*(++ptr) == '?')
+      {
+      bravalue = OP_BRA;
+
+      switch (*(++ptr))
+        {
+        case '#':
+        case 'i':
+        case 'm':
+        case 's':
+        case 'x':
+        ptr++;
+        while (*ptr != ')') ptr++;
+        previous = NULL;
+        continue;
+
+        case ':':                 /* Non-extracting bracket */
+        ptr++;
+        break;
+
+        case '=':                 /* Assertions can't be repeated */
+        bravalue = OP_ASSERT;
+        ptr++;
+        previous = NULL;
+        break;
+
+        case '!':
+        bravalue = OP_ASSERT_NOT;
+        ptr++;
+        previous = NULL;
+        break;
+
+        case '>':                         /* "Match once" brackets */
+        if ((options & PCRE_EXTRA) != 0)  /* Not yet standard */
+          {
+          bravalue = OP_ONCE;
+          ptr++;
+          previous = NULL;
+          break;
+          }
+        /* Else fall through */
+
+        default:
+        *errorptr = ERR12;
+        goto FAILED;
+        }
+      }
+
+    /* Else we have a referencing group */
+
+    else
+      {
+      if (++(*brackets) > EXTRACT_MAX)
+        {
+        *errorptr = ERR13;
+        goto FAILED;
+        }
+      bravalue = OP_BRA + *brackets;
+      }
+
+    /* Process nested bracketed re; at end pointer is on the bracket. We copy
+    code into a non-register variable in order to be able to pass its address
+    because some compilers complain otherwise. */
+
+    *code = bravalue;
+      {
+      uschar *mcode = code;
+      if (!compile_regex(options, brackets, &mcode, &ptr, errorptr))
+        goto FAILED;
+      code = mcode;
+      }
+
+    if (*ptr != ')')
+      {
+      *errorptr = ERR14;
+      goto FAILED;
+      }
+    break;
+
+    /* Check \ for being a real metacharacter; if not, fall through and handle
+    it as a data character at the start of a string. Escape items are checked
+    for validity in the pre-compiling pass. */
+
+    case '\\':
+    oldptr = ptr;
+    c = check_escape(&ptr, errorptr, *brackets, options, FALSE);
+
+    /* Handle metacharacters introduced by \. For ones like \d, the ESC_ values
+    are arranged to be the negation of the corresponding OP_values. For the
+    back references, the values are ESC_REF plus the reference number. Only
+    back references and those types that consume a character may be repeated.
+    We can test for values between ESC_b and ESC_Z for the latter; this may
+    have to change if any new ones are ever created. */
+
+    if (c < 0)
+      {
+      if (-c >= ESC_REF)
+        {
+        int refnum = -c - ESC_REF;
+        if (*brackets < refnum)
+          {
+          *errorptr = ERR15;
+          goto FAILED;
+          }
+        previous = code;
+        *code++ = OP_REF;
+        *code++ = refnum;
+        }
+      else
+        {
+        previous = (-c > ESC_b && -c < ESC_X)? code : NULL;
+        *code++ = -c;
+        }
+      continue;
+      }
+
+    /* Reset and fall through */
+
+    ptr = oldptr;
+    c = '\\';
+
+    /* Handle a run of data characters until a metacharacter is encountered.
+    The first character is guaranteed not to be whitespace or # when the
+    extended flag is set. */
+
+    NORMAL_CHAR:
+    default:
+    previous = code;
+    *code = OP_CHARS;
+    code += 2;
+    length = 0;
+
+    do
+      {
+      if ((options & PCRE_EXTENDED) != 0)
+        {
+        if ((pcre_ctypes[c] & ctype_space) != 0) continue;
+        if (c == '#')
+          {
+          while ((c = *(++ptr)) != 0 && c != '\n');
+          if (c == 0) break;
+          continue;
+          }
+        }
+
+      /* Backslash may introduce a data char or a metacharacter. Escaped items
+      are checked for validity in the pre-compiling pass. Stop the string
+      before a metaitem. */
+
+      if (c == '\\')
+        {
+        oldptr = ptr;
+        c = check_escape(&ptr, errorptr, *brackets, options, FALSE);
+        if (c < 0) { ptr = oldptr; break; }
+        }
+
+      /* Ordinary character or single-char escape */
+
+      *code++ = c;
+      length++;
+      }
+
+    /* This "while" is the end of the "do" above. */
+
+    while (length < 255 && (pcre_ctypes[c = *(++ptr)] & ctype_meta) == 0);
+
+    /* Compute the length and set it in the data vector, and advance to
+    the next state. */
+
+    previous[1] = length;
+    ptr--;
+    break;
+    }
+  }                   /* end of big loop */
+
+/* Control never reaches here by falling through, only by a goto for all the
+error states. Pass back the position in the pattern so that it can be displayed
+to the user for diagnosing the error. */
+
+FAILED:
+*ptrptr = ptr;
+return FALSE;
+}
+
+
+
+
+/*************************************************
+*     Compile sequence of alternatives           *
+*************************************************/
+
+/* On entry, ptr is pointing past the bracket character, but on return
+it points to the closing bracket, or vertical bar, or end of string.
+The code variable is pointing at the byte into which the BRA operator has been
+stored.
+
+Argument:
+  options   the option bits
+  brackets  -> int containing the number of extracting brackets used
+  codeptr   -> the address of the current code pointer
+  ptrptr    -> the address of the current pattern pointer
+  errorptr  -> pointer to error message
+
+Returns:    TRUE on success
+*/
+
+static BOOL
+compile_regex(int options, int *brackets, uschar **codeptr, uschar **ptrptr,
+  char **errorptr)
+{
+uschar *ptr = *ptrptr;
+uschar *code = *codeptr;
+uschar *start_bracket = code;
+
+for (;;)
+  {
+  int length;
+  uschar *last_branch = code;
+
+  code += 3;
+  if (!compile_branch(options, brackets, &code, &ptr, errorptr))
+    {
+    *ptrptr = ptr;
+    return FALSE;
+    }
+
+  /* Fill in the length of the last branch */
+
+  length = code - last_branch;
+  last_branch[1] = length >> 8;
+  last_branch[2] = length & 255;
+
+  /* Reached end of expression, either ')' or end of pattern. Insert a
+  terminating ket and the length of the whole bracketed item, and return,
+  leaving the pointer at the terminating char. */
+
+  if (*ptr != '|')
+    {
+    length = code - start_bracket;
+    *code++ = OP_KET;
+    *code++ = length >> 8;
+    *code++ = length & 255;
+    *codeptr = code;
+    *ptrptr = ptr;
+    return TRUE;
+    }
+
+  /* Another branch follows; insert an "or" node and advance the pointer. */
+
+  *code = OP_ALT;
+  ptr++;
+  }
+/* Control never reaches here */
+}
+
+
+
+/*************************************************
+*          Check for anchored expression         *
+*************************************************/
+
+/* Try to find out if this is an anchored regular expression. Consider each
+alternative branch. If they all start with OP_SOD or OP_CIRC, or with a bracket
+all of whose alternatives start with OP_SOD or OP_CIRC (recurse ad lib), then
+it's anchored. However, if this is a multiline pattern, then only OP_SOD
+counts, since OP_CIRC can match in the middle.
+
+A branch is also implicitly anchored if it starts with .* because that will try
+the rest of the pattern at all possible matching points, so there is no point
+trying them again.
+
+Argument:  points to start of expression (the bracket)
+Returns:   TRUE or FALSE
+*/
+
+static BOOL
+is_anchored(register uschar *code, BOOL multiline)
+{
+do {
+   int op = (int)code[3];
+   if (op >= OP_BRA || op == OP_ASSERT || op == OP_ONCE)
+     { if (!is_anchored(code+3, multiline)) return FALSE; }
+   else if (op == OP_TYPESTAR || op == OP_TYPEMINSTAR)
+     { if (code[4] != OP_ANY) return FALSE; }
+   else if (op != OP_SOD && (multiline || op != OP_CIRC)) return FALSE;
+   code += (code[1] << 8) + code[2];
+   }
+while (*code == OP_ALT);
+return TRUE;
+}
+
+
+
+/*************************************************
+*     Check for start with \n line expression    *
+*************************************************/
+
+/* This is called for multiline expressions to try to find out if every branch
+starts with ^ so that "first char" processing can be done to speed things up.
+
+Argument:  points to start of expression (the bracket)
+Returns:   TRUE or FALSE
+*/
+
+static BOOL
+is_startline(uschar *code)
+{
+do {
+   if ((int)code[3] >= OP_BRA || code[3] == OP_ASSERT)
+     { if (!is_startline(code+3)) return FALSE; }
+   else if (code[3] != OP_CIRC) return FALSE;
+   code += (code[1] << 8) + code[2];
+   }
+while (*code == OP_ALT);
+return TRUE;
+}
+
+
+
+/*************************************************
+*          Check for fixed first char            *
+*************************************************/
+
+/* Try to find out if there is a fixed first character. This is called for
+unanchored expressions, as it speeds up their processing quite considerably.
+Consider each alternative branch. If they all start with the same char, or with
+a bracket all of whose alternatives start with the same char (recurse ad lib),
+then we return that char, otherwise -1.
+
+Argument:  points to start of expression (the bracket)
+Returns:   -1 or the fixed first char
+*/
+
+static int
+find_firstchar(uschar *code)
+{
+register int c = -1;
+do
+  {
+  register int charoffset = 4;
+
+  if ((int)code[3] >= OP_BRA || code[3] == OP_ASSERT)
+    {
+    register int d;
+    if ((d = find_firstchar(code+3)) < 0) return -1;
+    if (c < 0) c = d; else if (c != d) return -1;
+    }
+
+  else switch(code[3])
+    {
+    default:
+    return -1;
+
+    case OP_EXACT:       /* Fall through */
+    charoffset++;
+
+    case OP_CHARS:       /* Fall through */
+    charoffset++;
+
+    case OP_PLUS:
+    case OP_MINPLUS:
+    if (c < 0) c = code[charoffset]; else if (c != code[charoffset]) return -1;
+    break;
+    }
+  code += (code[1] << 8) + code[2];
+  }
+while (*code == OP_ALT);
+return c;
+}
+
+
+
+/*************************************************
+*        Compile a Regular Expression            *
+*************************************************/
+
+/* This function takes a string and returns a pointer to a block of store
+holding a compiled version of the expression.
+
+Arguments:
+  pattern      the regular expression
+  options      various option bits
+  errorptr     pointer to pointer to error text
+  erroroffset  ptr offset in pattern where error was detected
+
+Returns:       pointer to compiled data block, or NULL on error,
+               with errorptr and erroroffset set
+*/
+
+pcre *
+pcre_compile(const char *pattern, int options, char **errorptr,
+  int *erroroffset)
+{
+real_pcre *re;
+int spaces = 0;
+int length = 3;      /* For initial BRA plus length */
+int runlength;
+int c, size;
+int bracount = 0;
+int brastack[200];
+int brastackptr = 0;
+int top_backref = 0;
+uschar *code, *ptr;
+
+#ifdef DEBUG
+uschar *code_base, *code_end;
+#endif
+
+/* We can't pass back an error message if errorptr is NULL; I guess the best we
+can do is just return NULL. */
+
+if (errorptr == NULL) return NULL;
+*errorptr = NULL;
+
+/* However, we can give a message for this error */
+
+if (erroroffset == NULL)
+  {
+  *errorptr = ERR16;
+  return NULL;
+  }
+*erroroffset = 0;
+
+if ((options & ~PUBLIC_OPTIONS) != 0)
+  {
+  *errorptr = ERR17;
+  return NULL;
+  }
+
+#ifdef DEBUG
+printf("------------------------------------------------------------------\n");
+printf("%s\n", pattern);
+#endif
+
+/* The first thing to do is to make a pass over the pattern to compute the
+amount of store required to hold the compiled code. This does not have to be
+perfect as long as errors are overestimates. At the same time we can detect any
+internal flag settings. Make an attempt to correct for any counted white space
+if an "extended" flag setting appears late in the pattern. We can't be so
+clever for #-comments. */
+
+ptr = (uschar *)(pattern - 1);
+while ((c = *(++ptr)) != 0)
+  {
+  int min, max;
+  int class_charcount;
+
+  if ((pcre_ctypes[c] & ctype_space) != 0)
+    {
+    if ((options & PCRE_EXTENDED) != 0) continue;
+    spaces++;
+    }
+
+  if (c == '#' && (options & PCRE_EXTENDED) != 0)
+    {
+    while ((c = *(++ptr)) != 0 && c != '\n');
+    continue;
+    }
+
+  switch(c)
+    {
+    /* A backslashed item may be an escaped "normal" character or a
+    character type. For a "normal" character, put the pointers and
+    character back so that tests for whitespace etc. in the input
+    are done correctly. */
+
+    case '\\':
+      {
+      uschar *save_ptr = ptr;
+      c = check_escape(&ptr, errorptr, bracount, options, FALSE);
+      if (*errorptr != NULL) goto PCRE_ERROR_RETURN;
+      if (c >= 0)
+        {
+        ptr = save_ptr;
+        c = '\\';
+        goto NORMAL_CHAR;
+        }
+      }
+    length++;
+
+    /* A back reference needs an additional char, plus either one or 5
+    bytes for a repeat. We also need to keep the value of the highest
+    back reference. */
+
+    if (c <= -ESC_REF)
+      {
+      int refnum = -c - ESC_REF;
+      if (refnum > top_backref) top_backref = refnum;
+      length++;   /* For single back reference */
+      if (ptr[1] == '{' && is_counted_repeat(ptr+2))
+        {
+        ptr = read_repeat_counts(ptr+2, &min, &max, errorptr);
+        if (*errorptr != NULL) goto PCRE_ERROR_RETURN;
+        if ((min == 0 && (max == 1 || max == -1)) ||
+          (min == 1 && max == -1))
+            length++;
+        else length += 5;
+        if (ptr[1] == '?') ptr++;
+        }
+      }
+    continue;
+
+    case '^':
+    case '.':
+    case '$':
+    case '*':     /* These repeats won't be after brackets; */
+    case '+':     /* those are handled separately */
+    case '?':
+    length++;
+    continue;
+
+    /* This covers the cases of repeats after a single char, metachar, class,
+    or back reference. */
+
+    case '{':
+    if (!is_counted_repeat(ptr+1)) goto NORMAL_CHAR;
+    ptr = read_repeat_counts(ptr+1, &min, &max, errorptr);
+    if (*errorptr != NULL) goto PCRE_ERROR_RETURN;
+    if ((min == 0 && (max == 1 || max == -1)) ||
+      (min == 1 && max == -1))
+        length++;
+    else
+      {
+      length--;   /* Uncount the original char or metachar */
+      if (min == 1) length++; else if (min > 0) length += 4;
+      if (max > 0) length += 4; else length += 2;
+      }
+    if (ptr[1] == '?') ptr++;
+    continue;
+
+    /* An alternation contains an offset to the next branch or ket. */
+    case '|':
+    length += 3;
+    continue;
+
+    /* A character class uses 33 characters. Don't worry about character types
+    that aren't allowed in classes - they'll get picked up during the compile.
+    A character class that contains only one character uses 2 or 3 bytes,
+    depending on whether it is negated or not. Notice this where we can. */
+
+    case '[':
+    class_charcount = 0;
+    if (*(++ptr) == '^') ptr++;
+    do
+      {
+      if (*ptr == '\\')
+        {
+        int c = check_escape(&ptr, errorptr, bracount, options, TRUE);
+        if (*errorptr != NULL) goto PCRE_ERROR_RETURN;
+        if (-c == ESC_b) class_charcount++; else class_charcount = 10;
+        }
+      else class_charcount++;
+      ptr++;
+      }
+    while (*ptr != 0 && *ptr != ']');
+
+    /* Repeats for negated single chars are handled by the general code */
+
+    if (class_charcount == 1) length += 3; else
+      {
+      length += 33;
+
+      /* A repeat needs either 1 or 5 bytes. */
+
+      if (ptr[1] == '{' && is_counted_repeat(ptr+2))
+        {
+        ptr = read_repeat_counts(ptr+2, &min, &max, errorptr);
+        if (*errorptr != NULL) goto PCRE_ERROR_RETURN;
+        if ((min == 0 && (max == 1 || max == -1)) ||
+          (min == 1 && max == -1))
+            length++;
+        else length += 5;
+        if (ptr[1] == '?') ptr++;
+        }
+      }
+    continue;
+
+    /* Brackets may be genuine groups or special things */
+
+    case '(':
+
+    /* Handle special forms of bracket, which all start (? */
+
+    if (ptr[1] == '?') switch (c = ptr[2])
+      {
+      /* Skip over comments entirely */
+      case '#':
+      ptr += 3;
+      while (*ptr != 0 && *ptr != ')') ptr++;
+      if (*ptr == 0)
+        {
+        *errorptr = ERR18;
+        goto PCRE_ERROR_RETURN;
+        }
+      continue;
+
+      /* Non-referencing groups and lookaheads just move the pointer on, and
+      then behave like a non-special bracket, except that they don't increment
+      the count of extracting brackets. */
+
+      case ':':
+      case '=':
+      case '!':
+      ptr += 2;
+      break;
+
+      /* Ditto for the "once only" bracket, allowed only if the extra bit
+      is set. */
+
+      case '>':
+      if ((options & PCRE_EXTRA) != 0)
+        {
+        ptr += 2;
+        break;
+        }
+      /* Else fall thourh */
+
+      /* Else loop setting valid options until ) is met. Anything else is an
+      error. */
+
+      default:
+      ptr += 2;
+      for (;; ptr++)
+        {
+        if ((c = *ptr) == 'i')
+          {
+          options |= PCRE_CASELESS;
+          continue;
+          }
+        else if ((c = *ptr) == 'm')
+          {
+          options |= PCRE_MULTILINE;
+          continue;
+          }
+        else if (c == 's')
+          {
+          options |= PCRE_DOTALL;
+          continue;
+          }
+        else if (c == 'x')
+          {
+          options |= PCRE_EXTENDED;
+          length -= spaces;          /* Already counted spaces */
+          continue;
+          }
+        else if (c == ')') break;
+
+        *errorptr = ERR12;
+        goto PCRE_ERROR_RETURN;
+        }
+      continue;                      /* End of this bracket handling */
+      }
+
+    /* Extracting brackets must be counted so we can process escapes in a
+    Perlish way. */
+
+    else bracount++;
+
+    /* Non-special forms of bracket. Save length for computing whole length
+    at end if there's a repeat that requires duplication of the group. */
+
+    if (brastackptr >= sizeof(brastack)/sizeof(int))
+      {
+      *errorptr = ERR19;
+      goto PCRE_ERROR_RETURN;
+      }
+
+    brastack[brastackptr++] = length;
+    length += 3;
+    continue;
+
+    /* Handle ket. Look for subsequent max/min; for certain sets of values we
+    have to replicate this bracket up to that many times. */
+
+    case ')':
+    length += 3;
+      {
+      int min = 1;
+      int max = 1;
+      int duplength = length - brastack[--brastackptr];
+
+      /* Leave ptr at the final char; for read_repeat_counts this happens
+      automatically; for the others we need an increment. */
+
+      if ((c = ptr[1]) == '{' && is_counted_repeat(ptr+2))
+        {
+        ptr = read_repeat_counts(ptr+2, &min, &max, errorptr);
+        if (*errorptr != NULL) goto PCRE_ERROR_RETURN;
+        }
+      else if (c == '*') { min = 0; max = -1; ptr++; }
+      else if (c == '+') { max = -1; ptr++; }
+      else if (c == '?') { min = 0; ptr++; }
+
+      /* If there is a minimum > 1 we have to replicate up to min-1 times; if
+      there is a limited maximum we have to replicate up to max-1 times and
+      allow for a BRAZERO item before each optional copy, as we also have to
+      do before the first copy if the minimum is zero. */
+
+      if (min == 0) length++;
+        else if (min > 1) length += (min - 1) * duplength;
+      if (max > min) length += (max - min) * (duplength + 1);
+      }
+
+    continue;
+
+    /* Non-special character. For a run of such characters the length required
+    is the number of characters + 2, except that the maximum run length is 255.
+    We won't get a skipped space or a non-data escape or the start of a #
+    comment as the first character, so the length can't be zero. */
+
+    NORMAL_CHAR:
+    default:
+    length += 2;
+    runlength = 0;
+    do
+      {
+      if ((pcre_ctypes[c] & ctype_space) != 0)
+        {
+        if ((options & PCRE_EXTENDED) != 0) continue;
+        spaces++;
+        }
+
+      if (c == '#' && (options & PCRE_EXTENDED) != 0)
+        {
+        while ((c = *(++ptr)) != 0 && c != '\n');
+        continue;
+        }
+
+      /* Backslash may introduce a data char or a metacharacter; stop the
+      string before the latter. */
+
+      if (c == '\\')
+        {
+        uschar *saveptr = ptr;
+        c = check_escape(&ptr, errorptr, bracount, options, FALSE);
+        if (*errorptr != NULL) goto PCRE_ERROR_RETURN;
+        if (c < 0) { ptr = saveptr; break; }
+        }
+
+      /* Ordinary character or single-char escape */
+
+      runlength++;
+      }
+
+    /* This "while" is the end of the "do" above. */
+
+    while (runlength < 255 && (pcre_ctypes[c = *(++ptr)] & ctype_meta) == 0);
+
+    ptr--;
+    length += runlength;
+    continue;
+    }
+  }
+
+length += 4;    /* For final KET and END */
+
+if (length > 65539)
+  {
+  *errorptr = ERR20;
+  return NULL;
+  }
+
+/* Compute the size of data block needed and get it, either from malloc or
+externally provided function. Put in the magic number and the options. */
+
+size = length + offsetof(real_pcre, code);
+re = (real_pcre *)(pcre_malloc)(size);
+
+if (re == NULL)
+  {
+  *errorptr = ERR21;
+  return NULL;
+  }
+
+re->magic_number = MAGIC_NUMBER;
+re->options = options;
+
+/* Set up a starting, non-extracting bracket, then compile the expression. On
+error, *errorptr will be set non-NULL, so we don't need to look at the result
+of the function here. */
+
+ptr = (uschar *)pattern;
+code = re->code;
+*code = OP_BRA;
+bracount = 0;
+(void)compile_regex(options, &bracount, &code, &ptr, errorptr);
+re->top_bracket = bracount;
+re->top_backref = top_backref;
+
+/* If not reached end of pattern on success, there's an excess bracket. */
+
+if (*errorptr == NULL && *ptr != 0) *errorptr = ERR22;
+
+/* Fill in the terminating state and check for disastrous overflow, but
+if debugging, leave the test till after things are printed out. */
+
+*code++ = OP_END;
+
+#ifndef DEBUG
+if (code - re->code > length) *errorptr = ERR23;
+#endif
+
+/* Failed to compile */
+
+if (*errorptr != NULL)
+  {
+  (pcre_free)(re);
+  PCRE_ERROR_RETURN:
+  *erroroffset = ptr - (uschar *)pattern;
+  return NULL;
+  }
+
+/* If the anchored option was not passed, set flag if we can determine that it
+is anchored by virtue of ^ characters or \A or anything else. Otherwise, see if
+we can determine what the first character has to be, because that speeds up
+unanchored matches no end. In the case of multiline matches, an alternative is
+to set the PCRE_STARTLINE flag if all branches start with ^. */
+
+if ((options & PCRE_ANCHORED) == 0)
+  {
+  if (is_anchored(re->code, (options & PCRE_MULTILINE) != 0))
+    re->options |= PCRE_ANCHORED;
+  else
+    {
+    int c = find_firstchar(re->code);
+    if (c >= 0)
+      {
+      re->first_char = c;
+      re->options |= PCRE_FIRSTSET;
+      }
+    else if (is_startline(re->code))
+      re->options |= PCRE_STARTLINE;
+    }
+  }
+
+/* Print out the compiled data for debugging */
+
+#ifdef DEBUG
+
+printf("Length = %d top_bracket = %d top_backref=%d\n",
+  length, re->top_bracket, re->top_backref);
+
+if (re->options != 0)
+  {
+  printf("%s%s%s%s%s%s%s\n",
+    ((re->options & PCRE_ANCHORED) != 0)? "anchored " : "",
+    ((re->options & PCRE_CASELESS) != 0)? "caseless " : "",
+    ((re->options & PCRE_EXTENDED) != 0)? "extended " : "",
+    ((re->options & PCRE_MULTILINE) != 0)? "multiline " : "",
+    ((re->options & PCRE_DOTALL) != 0)? "dotall " : "",
+    ((re->options & PCRE_DOLLAR_ENDONLY) != 0)? "endonly " : "",
+    ((re->options & PCRE_EXTRA) != 0)? "extra " : "");
+  }
+
+if ((re->options & PCRE_FIRSTSET) != 0)
+  {
+  if (isprint(re->first_char)) printf("First char = %c\n", re->first_char);
+    else printf("First char = \\x%02x\n", re->first_char);
+  }
+
+code_end = code;
+code_base = code = re->code;
+
+while (code < code_end)
+  {
+  int charlength;
+
+  printf("%3d ", code - code_base);
+
+  if (*code >= OP_BRA)
+    {
+    printf("%3d Bra %d", (code[1] << 8) + code[2], *code - OP_BRA);
+    code += 2;
+    }
+
+  else switch(*code)
+    {
+    case OP_CHARS:
+    charlength = *(++code);
+    printf("%3d ", charlength);
+    while (charlength-- > 0)
+      if (isprint(c = *(++code))) printf("%c", c); else printf("\\x%02x", c);
+    break;
+
+    case OP_KETRMAX:
+    case OP_KETRMIN:
+    case OP_ALT:
+    case OP_KET:
+    case OP_ASSERT:
+    case OP_ASSERT_NOT:
+    case OP_ONCE:
+    printf("%3d %s", (code[1] << 8) + code[2], OP_names[*code]);
+    code += 2;
+    break;
+
+    case OP_STAR:
+    case OP_MINSTAR:
+    case OP_PLUS:
+    case OP_MINPLUS:
+    case OP_QUERY:
+    case OP_MINQUERY:
+    case OP_TYPESTAR:
+    case OP_TYPEMINSTAR:
+    case OP_TYPEPLUS:
+    case OP_TYPEMINPLUS:
+    case OP_TYPEQUERY:
+    case OP_TYPEMINQUERY:
+    if (*code >= OP_TYPESTAR)
+      printf("    %s", OP_names[code[1]]);
+    else if (isprint(c = code[1])) printf("    %c", c);
+      else printf("    \\x%02x", c);
+    printf("%s", OP_names[*code++]);
+    break;
+
+    case OP_EXACT:
+    case OP_UPTO:
+    case OP_MINUPTO:
+    if (isprint(c = code[3])) printf("    %c{", c);
+      else printf("    \\x%02x{", c);
+    if (*code != OP_EXACT) printf(",");
+    printf("%d}", (code[1] << 8) + code[2]);
+    if (*code == OP_MINUPTO) printf("?");
+    code += 3;
+    break;
+
+    case OP_TYPEEXACT:
+    case OP_TYPEUPTO:
+    case OP_TYPEMINUPTO:
+    printf("    %s{", OP_names[code[3]]);
+    if (*code != OP_TYPEEXACT) printf(",");
+    printf("%d}", (code[1] << 8) + code[2]);
+    if (*code == OP_TYPEMINUPTO) printf("?");
+    code += 3;
+    break;
+
+    case OP_NOT:
+    if (isprint(c = *(++code))) printf("    [^%c]", c);
+      else printf("    [^\\x%02x]", c);
+    break;
+
+    case OP_NOTSTAR:
+    case OP_NOTMINSTAR:
+    case OP_NOTPLUS:
+    case OP_NOTMINPLUS:
+    case OP_NOTQUERY:
+    case OP_NOTMINQUERY:
+    if (isprint(c = code[1])) printf("    [^%c]", c);
+      else printf("    [^\\x%02x]", c);
+    printf("%s", OP_names[*code++]);
+    break;
+
+    case OP_NOTEXACT:
+    case OP_NOTUPTO:
+    case OP_NOTMINUPTO:
+    if (isprint(c = code[3])) printf("    [^%c]{", c);
+      else printf("    [^\\x%02x]{", c);
+    if (*code != OP_NOTEXACT) printf(",");
+    printf("%d}", (code[1] << 8) + code[2]);
+    if (*code == OP_NOTMINUPTO) printf("?");
+    code += 3;
+    break;
+
+    case OP_REF:
+    printf("    \\%d", *(++code));
+    break;
+
+    case OP_CLASS:
+      {
+      int i, min, max;
+
+      code++;
+      printf("    [");
+
+      for (i = 0; i < 256; i++)
+        {
+        if ((code[i/8] & (1 << (i&7))) != 0)
+          {
+          int j;
+          for (j = i+1; j < 256; j++)
+            if ((code[j/8] & (1 << (j&7))) == 0) break;
+          if (i == '-' || i == ']') printf("\\");
+          if (isprint(i)) printf("%c", i); else printf("\\x%02x", i);
+          if (--j > i)
+            {
+            printf("-");
+            if (j == '-' || j == ']') printf("\\");
+            if (isprint(j)) printf("%c", j); else printf("\\x%02x", j);
+            }
+          i = j;
+          }
+        }
+      printf("]");
+      code += 32;
+
+      switch(*code)
+        {
+        case OP_CRSTAR:
+        case OP_CRMINSTAR:
+        case OP_CRPLUS:
+        case OP_CRMINPLUS:
+        case OP_CRQUERY:
+        case OP_CRMINQUERY:
+        printf("%s", OP_names[*code]);
+        break;
+
+        case OP_CRRANGE:
+        case OP_CRMINRANGE:
+        min = (code[1] << 8) + code[2];
+        max = (code[3] << 8) + code[4];
+        if (max == 0) printf("{%d,}", min);
+        else printf("{%d,%d}", min, max);
+        if (*code == OP_CRMINRANGE) printf("?");
+        code += 4;
+        break;
+
+        default:
+        code--;
+        }
+      }
+    break;
+
+    /* Anything else is just a one-node item */
+
+    default:
+    printf("    %s", OP_names[*code]);
+    break;
+    }
+
+  code++;
+  printf("\n");
+  }
+printf("------------------------------------------------------------------\n");
+
+/* This check is done here in the debugging case so that the code that
+was compiled can be seen. */
+
+if (code - re->code > length)
+  {
+  *errorptr = ERR23;
+  (pcre_free)(re);
+  *erroroffset = ptr - (uschar *)pattern;
+  return NULL;
+  }
+#endif
+
+return (pcre *)re;
+}
+
+
+
+/*************************************************
+*        Match a character type                  *
+*************************************************/
+
+/* Not used in all the places it might be as it's sometimes faster
+to put the code inline.
+
+Arguments:
+  type        the character type
+  c           the character
+  dotall      the dotall flag
+
+Returns:      TRUE if character is of the type
+*/
+
+static BOOL
+match_type(int type, int c, BOOL dotall)
+{
+
+#ifdef DEBUG
+if (isprint(c)) printf("matching subject %c against ", c);
+  else printf("matching subject \\x%02x against ", c);
+printf("%s\n", OP_names[type]);
+#endif
+
+switch(type)
+  {
+  case OP_ANY:            return dotall || c != '\n';
+  case OP_NOT_DIGIT:      return (pcre_ctypes[c] & ctype_digit) == 0;
+  case OP_DIGIT:          return (pcre_ctypes[c] & ctype_digit) != 0;
+  case OP_NOT_WHITESPACE: return (pcre_ctypes[c] & ctype_space) == 0;
+  case OP_WHITESPACE:     return (pcre_ctypes[c] & ctype_space) != 0;
+  case OP_NOT_WORDCHAR:   return (pcre_ctypes[c] & ctype_word) == 0;
+  case OP_WORDCHAR:       return (pcre_ctypes[c] & ctype_word) != 0;
+  }
+return FALSE;
+}
+
+
+
+/*************************************************
+*          Match a back-reference                *
+*************************************************/
+
+/* If a back reference hasn't been set, the match fails.
+
+Arguments:
+  number      reference number
+  eptr        points into the subject
+  length      length to be matched
+  md          points to match data block
+
+Returns:      TRUE if matched
+*/
+
+static BOOL
+match_ref(int number, register uschar *eptr, int length, match_data *md)
+{
+uschar *p = md->start_subject + md->offset_vector[number];
+
+#ifdef DEBUG
+if (eptr >= md->end_subject)
+  printf("matching subject <null>");
+else
+  {
+  printf("matching subject ");
+  pchars(eptr, length, TRUE, md);
+  }
+printf(" against backref ");
+pchars(p, length, FALSE, md);
+printf("\n");
+#endif
+
+/* Always fail if not enough characters left */
+
+if (length > md->end_subject - p) return FALSE;
+
+/* Separate the caselesss case for speed */
+
+if (md->caseless)
+  { while (length-- > 0) if (pcre_lcc[*p++] != pcre_lcc[*eptr++]) return FALSE; }
+else
+  { while (length-- > 0) if (*p++ != *eptr++) return FALSE; }
+
+return TRUE;
+}
+
+
+
+/*************************************************
+*         Match from current position            *
+*************************************************/
+
+/* On entry ecode points to the first opcode, and eptr to the first character.
+
+Arguments:
+   eptr        pointer in subject
+   ecode       position in code
+   offset_top  current top pointer
+   md          pointer to "static" info for the match
+
+Returns:       TRUE if matched
+*/
+
+static BOOL
+match(register uschar *eptr, register uschar *ecode, int offset_top,
+  match_data *md)
+{
+for (;;)
+  {
+  int min, max, ctype;
+  register int i;
+  register int c;
+  BOOL minimize;
+
+  /* Opening bracket. Check the alternative branches in turn, failing if none
+  match. We have to set the start offset if required and there is space
+  in the offset vector so that it is available for subsequent back references
+  if the bracket matches. However, if the bracket fails, we must put back the
+  previous value of both offsets in case they were set by a previous copy of
+  the same bracket. Don't worry about setting the flag for the error case here;
+  that is handled in the code for KET. */
+
+  if ((int)*ecode >= OP_BRA)
+    {
+    int number = (*ecode - OP_BRA) << 1;
+    int save_offset1, save_offset2;
+
+    #ifdef DEBUG
+    printf("start bracket %d\n", number/2);
+    #endif
+
+    if (number > 0 && number < md->offset_end)
+      {
+      save_offset1 = md->offset_vector[number];
+      save_offset2 = md->offset_vector[number+1];
+      md->offset_vector[number] = eptr - md->start_subject;
+
+      #ifdef DEBUG
+      printf("saving %d %d\n", save_offset1, save_offset2);
+      #endif
+      }
+
+    /* Recurse for all the alternatives. */
+
+    do
+      {
+      if (match(eptr, ecode+3, offset_top, md)) return TRUE;
+      ecode += (ecode[1] << 8) + ecode[2];
+      }
+    while (*ecode == OP_ALT);
+
+    #ifdef DEBUG
+    printf("bracket %d failed\n", number/2);
+    #endif
+
+    if (number > 0 && number < md->offset_end)
+      {
+      md->offset_vector[number] = save_offset1;
+      md->offset_vector[number+1] = save_offset2;
+      }
+
+    return FALSE;
+    }
+
+  /* Other types of node can be handled by a switch */
+
+  switch(*ecode)
+    {
+    case OP_END:
+    md->end_match_ptr = eptr;          /* Record where we ended */
+    md->end_offset_top = offset_top;   /* and how many extracts were taken */
+    return TRUE;
+
+    /* The equivalent of Prolog's "cut" - if the rest doesn't match, the
+    whole thing doesn't match, so we have to get out via a longjmp(). */
+
+    case OP_CUT:
+    if (match(eptr, ecode+1, offset_top, md)) return TRUE;
+    longjmp(md->fail_env, 1);
+
+    /* Assertion brackets. Check the alternative branches in turn - the
+    matching won't pass the KET for an assertion. If any one branch matches,
+    the assertion is true. */
+
+    case OP_ASSERT:
+    do
+      {
+      if (match(eptr, ecode+3, offset_top, md)) break;
+      ecode += (ecode[1] << 8) + ecode[2];
+      }
+    while (*ecode == OP_ALT);
+    if (*ecode == OP_KET) return FALSE;
+
+    /* Continue from after the assertion, updating the offsets high water
+    mark, since extracts may have been taken during the assertion. */
+
+    do ecode += (ecode[1] << 8) + ecode[2]; while (*ecode == OP_ALT);
+    ecode += 3;
+    offset_top = md->end_offset_top;
+    continue;
+
+    /* Negative assertion: all branches must fail to match */
+
+    case OP_ASSERT_NOT:
+    do
+      {
+      if (match(eptr, ecode+3, offset_top, md)) return FALSE;
+      ecode += (ecode[1] << 8) + ecode[2];
+      }
+    while (*ecode == OP_ALT);
+    ecode += 3;
+    continue;
+
+    /* "Once" brackets are like assertion brackets except that after a match,
+    the point in the subject string is not moved back. Thus there can never be
+    a back into the brackets. Check the alternative branches in turn - the
+    matching won't pass the KET for this kind of subpattern. If any one branch
+    matches, we carry on, leaving the subject pointer. */
+
+    case OP_ONCE:
+    do
+      {
+      if (match(eptr, ecode+3, offset_top, md)) break;
+      ecode += (ecode[1] << 8) + ecode[2];
+      }
+    while (*ecode == OP_ALT);
+    if (*ecode == OP_KET) return FALSE;
+
+    /* Continue as from after the assertion, updating the offsets high water
+    mark, since extracts may have been taken. */
+
+    do ecode += (ecode[1] << 8) + ecode[2]; while (*ecode == OP_ALT);
+    ecode += 3;
+    offset_top = md->end_offset_top;
+    eptr = md->end_match_ptr;
+    continue;
+
+    /* An alternation is the end of a branch; scan along to find the end of the
+    bracketed group and go to there. */
+
+    case OP_ALT:
+    do ecode += (ecode[1] << 8) + ecode[2]; while (*ecode == OP_ALT);
+    break;
+
+    /* BRAZERO and BRAMINZERO occur just before a bracket group, indicating
+    that it may occur zero times. It may repeat infinitely, or not at all -
+    i.e. it could be ()* or ()? in the pattern. Brackets with fixed upper
+    repeat limits are compiled as a number of copies, with the optional ones
+    preceded by BRAZERO or BRAMINZERO. */
+
+    case OP_BRAZERO:
+      {
+      uschar *next = ecode+1;
+      if (match(eptr, next, offset_top, md)) return TRUE;
+      do next += (next[1] << 8) + next[2]; while (*next == OP_ALT);
+      ecode = next + 3;
+      }
+    break;
+
+    case OP_BRAMINZERO:
+      {
+      uschar *next = ecode+1;
+      do next += (next[1] << 8) + next[2]; while (*next == OP_ALT);
+      if (match(eptr, next+3, offset_top, md)) return TRUE;
+      ecode++;
+      }
+    break;;
+
+    /* End of a group, repeated or non-repeating. If we are at the end of
+    an assertion "group", stop matching and return TRUE, but record the
+    current high water mark for use by positive assertions. */
+
+    case OP_KET:
+    case OP_KETRMIN:
+    case OP_KETRMAX:
+      {
+      int number;
+      uschar *prev = ecode - (ecode[1] << 8) - ecode[2];
+
+      if (*prev == OP_ASSERT || *prev == OP_ASSERT_NOT || *prev == OP_ONCE)
+        {
+        md->end_match_ptr = eptr;      /* For ONCE */
+        md->end_offset_top = offset_top;
+        return TRUE;
+        }
+
+      /* In all other cases we have to check the group number back at the
+      start and if necessary complete handling an extraction by setting the
+      final offset and bumping the high water mark. */
+
+      number = (*prev - OP_BRA) << 1;
+
+      #ifdef DEBUG
+      printf("end bracket %d\n", number/2);
+      #endif
+
+      if (number > 0)
+        {
+        if (number >= md->offset_end) md->offset_overflow = TRUE; else
+          {
+          md->offset_vector[number+1] = eptr - md->start_subject;
+          if (offset_top <= number) offset_top = number + 2;
+          }
+        }
+
+      /* For a non-repeating ket, just advance to the next node and continue at
+      this level. */
+
+      if (*ecode == OP_KET)
+        {
+        ecode += 3;
+        break;
+        }
+
+      /* The repeating kets try the rest of the pattern or restart from the
+      preceding bracket, in the appropriate order. */
+
+      if (*ecode == OP_KETRMIN)
+        {
+        if (match(eptr, ecode+3, offset_top, md) ||
+            match(eptr, prev, offset_top, md)) return TRUE;
+        }
+      else  /* OP_KETRMAX */
+        {
+        if (match(eptr, prev, offset_top, md) ||
+            match(eptr, ecode+3, offset_top, md)) return TRUE;
+        }
+      }
+    return FALSE;
+
+    /* Start of subject unless notbol, or after internal newline if multiline */
+
+    case OP_CIRC:
+    if (md->notbol && eptr == md->start_subject) return FALSE;
+    if (md->multiline)
+      {
+      if (eptr != md->start_subject && eptr[-1] != '\n') return FALSE;
+      ecode++;
+      break;
+      }
+    /* ... else fall through */
+
+    /* Start of subject assertion */
+
+    case OP_SOD:
+    if (eptr != md->start_subject) return FALSE;
+    ecode++;
+    break;
+
+    /* Assert before internal newline if multiline, or before
+    a terminating newline unless endonly is set, else end of subject unless
+    noteol is set. */
+
+    case OP_DOLL:
+    if (md->noteol && eptr >= md->end_subject) return FALSE;
+    if (md->multiline)
+      {
+      if (eptr < md->end_subject && *eptr != '\n') return FALSE;
+      ecode++;
+      break;
+      }
+    else if (!md->endonly)
+      {
+      if (eptr < md->end_subject - 1 ||
+         (eptr == md->end_subject - 1 && *eptr != '\n')) return FALSE;
+      ecode++;
+      break;
+      }
+    /* ... else fall through */
+
+    /* End of subject assertion */
+
+    case OP_EOD:
+    if (eptr < md->end_subject) return FALSE;
+    ecode++;
+    break;
+
+    /* Word boundary assertions */
+
+    case OP_NOT_WORD_BOUNDARY:
+    case OP_WORD_BOUNDARY:
+      {
+      BOOL prev_is_word = (eptr != md->start_subject) &&
+        ((pcre_ctypes[eptr[-1]] & ctype_word) != 0);
+      BOOL cur_is_word = (eptr < md->end_subject) &&
+        ((pcre_ctypes[*eptr] & ctype_word) != 0);
+      if ((*ecode++ == OP_WORD_BOUNDARY)?
+           cur_is_word == prev_is_word : cur_is_word != prev_is_word)
+        return FALSE;
+      }
+    break;
+
+    /* Match a single character type; inline for speed */
+
+    case OP_ANY:
+    if (!md->dotall && eptr < md->end_subject && *eptr == '\n') return FALSE;
+    if (eptr++ >= md->end_subject) return FALSE;
+    ecode++;
+    break;
+
+    case OP_NOT_DIGIT:
+    if (eptr >= md->end_subject || (pcre_ctypes[*eptr++] & ctype_digit) != 0)
+      return FALSE;
+    ecode++;
+    break;
+
+    case OP_DIGIT:
+    if (eptr >= md->end_subject || (pcre_ctypes[*eptr++] & ctype_digit) == 0)
+      return FALSE;
+    ecode++;
+    break;
+
+    case OP_NOT_WHITESPACE:
+    if (eptr >= md->end_subject || (pcre_ctypes[*eptr++] & ctype_space) != 0)
+      return FALSE;
+    ecode++;
+    break;
+
+    case OP_WHITESPACE:
+    if (eptr >= md->end_subject || (pcre_ctypes[*eptr++] & ctype_space) == 0)
+      return FALSE;
+    ecode++;
+    break;
+
+    case OP_NOT_WORDCHAR:
+    if (eptr >= md->end_subject || (pcre_ctypes[*eptr++] & ctype_word) != 0)
+      return FALSE;
+    ecode++;
+    break;
+
+    case OP_WORDCHAR:
+    if (eptr >= md->end_subject || (pcre_ctypes[*eptr++] & ctype_word) == 0)
+      return FALSE;
+    ecode++;
+    break;
+
+    /* Match a back reference, possibly repeatedly. Look past the end of the
+    item to see if there is repeat information following. The code is similar
+    to that for character classes, but repeated for efficiency. Then obey
+    similar code to character type repeats - written out again for speed.
+    However, if the referenced string is the empty string, always treat
+    it as matched, any number of times (otherwise there could be infinite
+    loops). */
+
+    case OP_REF:
+      {
+      int length;
+      int number = ecode[1] << 1;                /* Doubled reference number */
+      ecode += 2;                                /* Advance past the item */
+
+      if (number >= offset_top || md->offset_vector[number] < 0)
+        {
+        md->errorcode = PCRE_ERROR_BADREF;
+        return FALSE;
+        }
+
+      length = md->offset_vector[number+1] - md->offset_vector[number];
+
+      switch (*ecode)
+        {
+        case OP_CRSTAR:
+        case OP_CRMINSTAR:
+        case OP_CRPLUS:
+        case OP_CRMINPLUS:
+        case OP_CRQUERY:
+        case OP_CRMINQUERY:
+        c = *ecode++ - OP_CRSTAR;
+        minimize = (c & 1) != 0;
+        min = rep_min[c];                 /* Pick up values from tables; */
+        max = rep_max[c];                 /* zero for max => infinity */
+        if (max == 0) max = INT_MAX;
+        break;
+
+        case OP_CRRANGE:
+        case OP_CRMINRANGE:
+        minimize = (*ecode == OP_CRMINRANGE);
+        min = (ecode[1] << 8) + ecode[2];
+        max = (ecode[3] << 8) + ecode[4];
+        if (max == 0) max = INT_MAX;
+        ecode += 5;
+        break;
+
+        default:               /* No repeat follows */
+        if (!match_ref(number, eptr, length, md)) return FALSE;
+        eptr += length;
+        continue;              /* With the main loop */
+        }
+
+      /* If the length of the reference is zero, just continue with the
+      main loop. */
+
+      if (length == 0) continue;
+
+      /* First, ensure the minimum number of matches are present. We get back
+      the length of the reference string explicitly rather than passing the
+      address of eptr, so that eptr can be a register variable. */
+
+      for (i = 1; i <= min; i++)
+        {
+        if (!match_ref(number, eptr, length, md)) return FALSE;
+        eptr += length;
+        }
+
+      /* If min = max, continue at the same level without recursion.
+      They are not both allowed to be zero. */
+
+      if (min == max) continue;
+
+      /* If minimizing, keep trying and advancing the pointer */
+
+      if (minimize)
+        {
+        for (i = min;; i++)
+          {
+          if (match(eptr, ecode, offset_top, md)) return TRUE;
+          if (i >= max || !match_ref(number, eptr, length, md))
+            return FALSE;
+          eptr += length;
+          }
+        /* Control never gets here */
+        }
+
+      /* If maximizing, find the longest string and work backwards */
+
+      else
+        {
+        uschar *pp = eptr;
+        for (i = min; i < max; i++)
+          {
+          if (!match_ref(number, eptr, length, md)) break;
+          eptr += length;
+          }
+        while (eptr >= pp)
+          {
+          if (match(eptr, ecode, offset_top, md)) return TRUE;
+          eptr -= length;
+          }
+        return FALSE;
+        }
+      }
+    /* Control never gets here */
+
+    /* Match a character class, possibly repeatedly. Look past the end of the
+    item to see if there is repeat information following. Then obey similar
+    code to character type repeats - written out again for speed. If caseless
+    matching was set at runtime but not at compile time, we have to check both
+    versions of a character. */
+
+    case OP_CLASS:
+      {
+      uschar *data = ecode + 1;  /* Save for matching */
+      ecode += 33;               /* Advance past the item */
+
+      switch (*ecode)
+        {
+        case OP_CRSTAR:
+        case OP_CRMINSTAR:
+        case OP_CRPLUS:
+        case OP_CRMINPLUS:
+        case OP_CRQUERY:
+        case OP_CRMINQUERY:
+        c = *ecode++ - OP_CRSTAR;
+        minimize = (c & 1) != 0;
+        min = rep_min[c];                 /* Pick up values from tables; */
+        max = rep_max[c];                 /* zero for max => infinity */
+        if (max == 0) max = INT_MAX;
+        break;
+
+        case OP_CRRANGE:
+        case OP_CRMINRANGE:
+        minimize = (*ecode == OP_CRMINRANGE);
+        min = (ecode[1] << 8) + ecode[2];
+        max = (ecode[3] << 8) + ecode[4];
+        if (max == 0) max = INT_MAX;
+        ecode += 5;
+        break;
+
+        default:               /* No repeat follows */
+        if (eptr >= md->end_subject) return FALSE;
+        c = *eptr++;
+        if ((data[c/8] & (1 << (c&7))) != 0) continue;    /* With main loop */
+        if (md->runtime_caseless)
+          {
+          c = pcre_fcc[c];
+          if ((data[c/8] & (1 << (c&7))) != 0) continue;  /* With main loop */
+          }
+        return FALSE;
+        }
+
+      /* First, ensure the minimum number of matches are present. */
+
+      for (i = 1; i <= min; i++)
+        {
+        if (eptr >= md->end_subject) return FALSE;
+        c = *eptr++;
+        if ((data[c/8] & (1 << (c&7))) != 0) continue;
+        if (md->runtime_caseless)
+          {
+          c = pcre_fcc[c];
+          if ((data[c/8] & (1 << (c&7))) != 0) continue;
+          }
+        return FALSE;
+        }
+
+      /* If max == min we can continue with the main loop without the
+      need to recurse. */
+
+      if (min == max) continue;
+
+      /* If minimizing, keep testing the rest of the expression and advancing
+      the pointer while it matches the class. */
+
+      if (minimize)
+        {
+        for (i = min;; i++)
+          {
+          if (match(eptr, ecode, offset_top, md)) return TRUE;
+          if (i >= max || eptr >= md->end_subject) return FALSE;
+          c = *eptr++;
+          if ((data[c/8] & (1 << (c&7))) != 0) continue;
+          if (md->runtime_caseless)
+            {
+            c = pcre_fcc[c];
+            if ((data[c/8] & (1 << (c&7))) != 0) continue;
+            }
+          return FALSE;
+          }
+        /* Control never gets here */
+        }
+
+      /* If maximizing, find the longest possible run, then work backwards. */
+
+      else
+        {
+        uschar *pp = eptr;
+        for (i = min; i < max; eptr++, i++)
+          {
+          if (eptr >= md->end_subject) break;
+          c = *eptr;
+          if ((data[c/8] & (1 << (c&7))) != 0) continue;
+          if (md->runtime_caseless)
+            {
+            c = pcre_fcc[c];
+            if ((data[c/8] & (1 << (c&7))) != 0) continue;
+            }
+          break;
+          }
+
+        while (eptr >= pp)
+          if (match(eptr--, ecode, offset_top, md)) return TRUE;
+        return FALSE;
+        }
+      }
+    /* Control never gets here */
+
+    /* Match a run of characters */
+
+    case OP_CHARS:
+      {
+      register int length = ecode[1];
+      ecode += 2;
+
+      #ifdef DEBUG
+      if (eptr >= md->end_subject)
+        printf("matching subject <null> against pattern ");
+      else
+        {
+        printf("matching subject ");
+        pchars(eptr, length, TRUE, md);
+        printf(" against pattern ");
+        }
+      pchars(ecode, length, FALSE, md);
+      printf("\n");
+      #endif
+
+      if (length > md->end_subject - eptr) return FALSE;
+      if (md->caseless)
+        {
+        while (length-- > 0) if (pcre_lcc[*ecode++] != pcre_lcc[*eptr++]) return FALSE;
+        }
+      else
+        {
+        while (length-- > 0) if (*ecode++ != *eptr++) return FALSE;
+        }
+      }
+    break;
+
+    /* Match a single character repeatedly; different opcodes share code. */
+
+    case OP_EXACT:
+    min = max = (ecode[1] << 8) + ecode[2];
+    ecode += 3;
+    goto REPEATCHAR;
+
+    case OP_UPTO:
+    case OP_MINUPTO:
+    min = 0;
+    max = (ecode[1] << 8) + ecode[2];
+    minimize = *ecode == OP_MINUPTO;
+    ecode += 3;
+    goto REPEATCHAR;
+
+    case OP_STAR:
+    case OP_MINSTAR:
+    case OP_PLUS:
+    case OP_MINPLUS:
+    case OP_QUERY:
+    case OP_MINQUERY:
+    c = *ecode++ - OP_STAR;
+    minimize = (c & 1) != 0;
+    min = rep_min[c];                 /* Pick up values from tables; */
+    max = rep_max[c];                 /* zero for max => infinity */
+    if (max == 0) max = INT_MAX;
+
+    /* Common code for all repeated single-character matches. We can give
+    up quickly if there are fewer than the minimum number of characters left in
+    the subject. */
+
+    REPEATCHAR:
+    if (min > md->end_subject - eptr) return FALSE;
+    c = *ecode++;
+
+    /* The code is duplicated for the caseless and caseful cases, for speed,
+    since matching characters is likely to be quite common. First, ensure the
+    minimum number of matches are present. If min = max, continue at the same
+    level without recursing. Otherwise, if minimizing, keep trying the rest of
+    the expression and advancing one matching character if failing, up to the
+    maximum. Alternatively, if maximizing, find the maximum number of
+    characters and work backwards. */
+
+    #ifdef DEBUG
+    printf("matching %c{%d,%d} against subject %.*s\n", c, min, max,
+      max, eptr);
+    #endif
+
+    if (md->caseless)
+      {
+      c = pcre_lcc[c];
+      for (i = 1; i <= min; i++) if (c != pcre_lcc[*eptr++]) return FALSE;
+      if (min == max) continue;
+      if (minimize)
+        {
+        for (i = min;; i++)
+          {
+          if (match(eptr, ecode, offset_top, md)) return TRUE;
+          if (i >= max || eptr >= md->end_subject || c != pcre_lcc[*eptr++])
+            return FALSE;
+          }
+        /* Control never gets here */
+        }
+      else
+        {
+        uschar *pp = eptr;
+        for (i = min; i < max; i++)
+          {
+          if (eptr >= md->end_subject || c != pcre_lcc[*eptr]) break;
+          eptr++;
+          }
+        while (eptr >= pp)
+          if (match(eptr--, ecode, offset_top, md)) return TRUE;
+        return FALSE;
+        }
+      /* Control never gets here */
+      }
+
+    /* Caseful comparisons */
+
+    else
+      {
+      for (i = 1; i <= min; i++) if (c != *eptr++) return FALSE;
+      if (min == max) continue;
+      if (minimize)
+        {
+        for (i = min;; i++)
+          {
+          if (match(eptr, ecode, offset_top, md)) return TRUE;
+          if (i >= max || eptr >= md->end_subject || c != *eptr++) return FALSE;
+          }
+        /* Control never gets here */
+        }
+      else
+        {
+        uschar *pp = eptr;
+        for (i = min; i < max; i++)
+          {
+          if (eptr >= md->end_subject || c != *eptr) break;
+          eptr++;
+          }
+        while (eptr >= pp)
+         if (match(eptr--, ecode, offset_top, md)) return TRUE;
+        return FALSE;
+        }
+      }
+    /* Control never gets here */
+
+    /* Match a negated single character */
+
+    case OP_NOT:
+    if (eptr > md->end_subject) return FALSE;
+    ecode++;
+    if (md->caseless)
+      {
+      if (pcre_lcc[*ecode++] == pcre_lcc[*eptr++]) return FALSE;
+      }
+    else
+      {
+      if (*ecode++ == *eptr++) return FALSE;
+      }
+    break;
+
+    /* Match a negated single character repeatedly. This is almost a repeat of
+    the code for a repeated single character, but I haven't found a nice way of
+    commoning these up that doesn't require a test of the positive/negative
+    option for each character match. Maybe that wouldn't add very much to the
+    time taken, but character matching *is* what this is all about... */
+
+    case OP_NOTEXACT:
+    min = max = (ecode[1] << 8) + ecode[2];
+    ecode += 3;
+    goto REPEATNOTCHAR;
+
+    case OP_NOTUPTO:
+    case OP_NOTMINUPTO:
+    min = 0;
+    max = (ecode[1] << 8) + ecode[2];
+    minimize = *ecode == OP_NOTMINUPTO;
+    ecode += 3;
+    goto REPEATNOTCHAR;
+
+    case OP_NOTSTAR:
+    case OP_NOTMINSTAR:
+    case OP_NOTPLUS:
+    case OP_NOTMINPLUS:
+    case OP_NOTQUERY:
+    case OP_NOTMINQUERY:
+    c = *ecode++ - OP_NOTSTAR;
+    minimize = (c & 1) != 0;
+    min = rep_min[c];                 /* Pick up values from tables; */
+    max = rep_max[c];                 /* zero for max => infinity */
+    if (max == 0) max = INT_MAX;
+
+    /* Common code for all repeated single-character matches. We can give
+    up quickly if there are fewer than the minimum number of characters left in
+    the subject. */
+
+    REPEATNOTCHAR:
+    if (min > md->end_subject - eptr) return FALSE;
+    c = *ecode++;
+
+    /* The code is duplicated for the caseless and caseful cases, for speed,
+    since matching characters is likely to be quite common. First, ensure the
+    minimum number of matches are present. If min = max, continue at the same
+    level without recursing. Otherwise, if minimizing, keep trying the rest of
+    the expression and advancing one matching character if failing, up to the
+    maximum. Alternatively, if maximizing, find the maximum number of
+    characters and work backwards. */
+
+    #ifdef DEBUG
+    printf("negative matching %c{%d,%d} against subject %.*s\n", c, min, max,
+      max, eptr);
+    #endif
+
+    if (md->caseless)
+      {
+      c = pcre_lcc[c];
+      for (i = 1; i <= min; i++) if (c == pcre_lcc[*eptr++]) return FALSE;
+      if (min == max) continue;
+      if (minimize)
+        {
+        for (i = min;; i++)
+          {
+          if (match(eptr, ecode, offset_top, md)) return TRUE;
+          if (i >= max || eptr >= md->end_subject || c == pcre_lcc[*eptr++])
+            return FALSE;
+          }
+        /* Control never gets here */
+        }
+      else
+        {
+        uschar *pp = eptr;
+        for (i = min; i < max; i++)
+          {
+          if (eptr >= md->end_subject || c == pcre_lcc[*eptr]) break;
+          eptr++;
+          }
+        while (eptr >= pp)
+          if (match(eptr--, ecode, offset_top, md)) return TRUE;
+        return FALSE;
+        }
+      /* Control never gets here */
+      }
+
+    /* Caseful comparisons */
+
+    else
+      {
+      for (i = 1; i <= min; i++) if (c == *eptr++) return FALSE;
+      if (min == max) continue;
+      if (minimize)
+        {
+        for (i = min;; i++)
+          {
+          if (match(eptr, ecode, offset_top, md)) return TRUE;
+          if (i >= max || eptr >= md->end_subject || c == *eptr++) return FALSE;
+          }
+        /* Control never gets here */
+        }
+      else
+        {
+        uschar *pp = eptr;
+        for (i = min; i < max; i++)
+          {
+          if (eptr >= md->end_subject || c == *eptr) break;
+          eptr++;
+          }
+        while (eptr >= pp)
+         if (match(eptr--, ecode, offset_top, md)) return TRUE;
+        return FALSE;
+        }
+      }
+    /* Control never gets here */
+
+    /* Match a single character type repeatedly; several different opcodes
+    share code. This is very similar to the code for single characters, but we
+    repeat it in the interests of efficiency. */
+
+    case OP_TYPEEXACT:
+    min = max = (ecode[1] << 8) + ecode[2];
+    minimize = TRUE;
+    ecode += 3;
+    goto REPEATTYPE;
+
+    case OP_TYPEUPTO:
+    case OP_TYPEMINUPTO:
+    min = 0;
+    max = (ecode[1] << 8) + ecode[2];
+    minimize = *ecode == OP_TYPEMINUPTO;
+    ecode += 3;
+    goto REPEATTYPE;
+
+    case OP_TYPESTAR:
+    case OP_TYPEMINSTAR:
+    case OP_TYPEPLUS:
+    case OP_TYPEMINPLUS:
+    case OP_TYPEQUERY:
+    case OP_TYPEMINQUERY:
+    c = *ecode++ - OP_TYPESTAR;
+    minimize = (c & 1) != 0;
+    min = rep_min[c];                 /* Pick up values from tables; */
+    max = rep_max[c];                 /* zero for max => infinity */
+    if (max == 0) max = INT_MAX;
+
+    /* Common code for all repeated single character type matches */
+
+    REPEATTYPE:
+    ctype = *ecode++;      /* Code for the character type */
+
+    /* First, ensure the minimum number of matches are present. Use inline
+    code for maximizing the speed, and do the type test once at the start
+    (i.e. keep it out of the loop). Also test that there are at least the
+    minimum number of characters before we start. */
+
+    if (min > md->end_subject - eptr) return FALSE;
+    if (min > 0) switch(ctype)
+      {
+      case OP_ANY:
+      if (!md->dotall)
+        { for (i = 1; i <= min; i++) if (*eptr++ == '\n') return FALSE; }
+      else eptr += min;
+      break;
+
+      case OP_NOT_DIGIT:
+      for (i = 1; i <= min; i++)
+        if ((pcre_ctypes[*eptr++] & ctype_digit) != 0) return FALSE;
+      break;
+
+      case OP_DIGIT:
+      for (i = 1; i <= min; i++)
+        if ((pcre_ctypes[*eptr++] & ctype_digit) == 0) return FALSE;
+      break;
+
+      case OP_NOT_WHITESPACE:
+      for (i = 1; i <= min; i++)
+        if ((pcre_ctypes[*eptr++] & ctype_space) != 0) return FALSE;
+      break;
+
+      case OP_WHITESPACE:
+      for (i = 1; i <= min; i++)
+        if ((pcre_ctypes[*eptr++] & ctype_space) == 0) return FALSE;
+      break;
+
+      case OP_NOT_WORDCHAR:
+      for (i = 1; i <= min; i++) if ((pcre_ctypes[*eptr++] & ctype_word) != 0)
+        return FALSE;
+      break;
+
+      case OP_WORDCHAR:
+      for (i = 1; i <= min; i++) if ((pcre_ctypes[*eptr++] & ctype_word) == 0)
+        return FALSE;
+      break;
+      }
+
+    /* If min = max, continue at the same level without recursing */
+
+    if (min == max) continue;
+
+    /* If minimizing, we have to test the rest of the pattern before each
+    subsequent match, so inlining isn't much help; just use the function. */
+
+    if (minimize)
+      {
+      for (i = min;; i++)
+        {
+        if (match(eptr, ecode, offset_top, md)) return TRUE;
+        if (i >= max || eptr >= md->end_subject ||
+          !match_type(ctype, *eptr++, md->dotall))
+            return FALSE;
+        }
+      /* Control never gets here */
+      }
+
+    /* If maximizing it is worth using inline code for speed, doing the type
+    test once at the start (i.e. keep it out of the loop). */
+
+    else
+      {
+      uschar *pp = eptr;
+      switch(ctype)
+        {
+        case OP_ANY:
+        if (!md->dotall)
+          {
+          for (i = min; i < max; i++)
+            {
+            if (eptr >= md->end_subject || *eptr == '\n') break;
+            eptr++;
+            }
+          }
+        else
+          {
+          c = max - min;
+          if (c > md->end_subject - eptr) c = md->end_subject - eptr;
+          eptr += c;
+          }
+        break;
+
+        case OP_NOT_DIGIT:
+        for (i = min; i < max; i++)
+          {
+          if (eptr >= md->end_subject || (pcre_ctypes[*eptr] & ctype_digit) != 0)
+            break;
+          eptr++;
+          }
+        break;
+
+        case OP_DIGIT:
+        for (i = min; i < max; i++)
+          {
+          if (eptr >= md->end_subject || (pcre_ctypes[*eptr] & ctype_digit) == 0)
+            break;
+          eptr++;
+          }
+        break;
+
+        case OP_NOT_WHITESPACE:
+        for (i = min; i < max; i++)
+          {
+          if (eptr >= md->end_subject || (pcre_ctypes[*eptr] & ctype_space) != 0)
+            break;
+          eptr++;
+          }
+        break;
+
+        case OP_WHITESPACE:
+        for (i = min; i < max; i++)
+          {
+          if (eptr >= md->end_subject || (pcre_ctypes[*eptr] & ctype_space) == 0)
+            break;
+          eptr++;
+          }
+        break;
+
+        case OP_NOT_WORDCHAR:
+        for (i = min; i < max; i++)
+          {
+          if (eptr >= md->end_subject || (pcre_ctypes[*eptr] & ctype_word) != 0)
+            break;
+          eptr++;
+          }
+        break;
+
+        case OP_WORDCHAR:
+        for (i = min; i < max; i++)
+          {
+          if (eptr >= md->end_subject || (pcre_ctypes[*eptr] & ctype_word) == 0)
+            break;
+          eptr++;
+          }
+        break;
+        }
+
+      while (eptr >= pp)
+        if (match(eptr--, ecode, offset_top, md)) return TRUE;
+      return FALSE;
+      }
+    /* Control never gets here */
+
+    /* There's been some horrible disaster. */
+
+    default:
+    #ifdef DEBUG
+    printf("Unknown opcode %d\n", *ecode);
+    #endif
+    md->errorcode = PCRE_ERROR_UNKNOWN_NODE;
+    return FALSE;
+    }
+
+  /* Do not stick any code in here without much thought; it is assumed
+  that "continue" in the code above comes out to here to repeat the main
+  loop. */
+
+  }             /* End of main loop */
+/* Control never reaches here */
+}
+
+
+
+/*************************************************
+*         Execute a Regular Expression           *
+*************************************************/
+
+/* This function applies a compiled re to a subject string and picks out
+portions of the string if it matches. Two elements in the vector are set for
+each substring: the offsets to the start and end of the substring.
+
+Arguments:
+  external_re     points to the compiled expression
+  external_extra  points to "hints" from pcre_study() or is NULL
+  subject         points to the subject string
+  length          length of subject string (may contain binary zeros)
+  options         option bits
+  offsets         points to a vector of ints to be filled in with offsets
+  offsetcount     the number of elements in the vector
+
+Returns:          > 0 => success; value is the number of elements filled in
+                  = 0 => success, but offsets is not big enough
+                   -1 => failed to match
+                 < -1 => some kind of unexpected problem
+*/
+
+int
+pcre_exec(const pcre *external_re, const pcre_extra *external_extra,
+  const char *subject, int length, int options, int *offsets, int offsetcount)
+{
+int resetcount;
+int ocount = offsetcount;
+int first_char = -1;
+match_data match_block;
+uschar *start_bits = NULL;
+uschar *start_match = (uschar *)subject;
+uschar *end_subject;
+real_pcre *re = (real_pcre *)external_re;
+real_pcre_extra *extra = (real_pcre_extra *)external_extra;
+BOOL anchored = ((re->options | options) & PCRE_ANCHORED) != 0;
+BOOL startline = (re->options & PCRE_STARTLINE) != 0;
+
+if ((options & ~PUBLIC_EXEC_OPTIONS) != 0) return PCRE_ERROR_BADOPTION;
+
+if (re == NULL || subject == NULL ||
+   (offsets == NULL && offsetcount > 0)) return PCRE_ERROR_NULL;
+if (re->magic_number != MAGIC_NUMBER) return PCRE_ERROR_BADMAGIC;
+
+match_block.start_subject = (uschar *)subject;
+match_block.end_subject = match_block.start_subject + length;
+end_subject = match_block.end_subject;
+
+match_block.caseless  = ((re->options | options) & PCRE_CASELESS) != 0;
+match_block.runtime_caseless = match_block.caseless &&
+  (re->options & PCRE_CASELESS) == 0;
+
+match_block.multiline = ((re->options | options) & PCRE_MULTILINE) != 0;
+match_block.dotall    = ((re->options | options) & PCRE_DOTALL) != 0;
+match_block.endonly   = ((re->options | options) & PCRE_DOLLAR_ENDONLY) != 0;
+
+match_block.notbol = (options & PCRE_NOTBOL) != 0;
+match_block.noteol = (options & PCRE_NOTEOL) != 0;
+
+match_block.errorcode = PCRE_ERROR_NOMATCH;     /* Default error */
+
+/* If the expression has got more back references than the offsets supplied can
+hold, we get a temporary bit of working store to use during the matching.
+Otherwise, we can use the vector supplied, rounding down the size of it to a
+multiple of 2. */
+
+ocount &= (-2);
+if (re->top_backref > 0 && re->top_backref + 1 >= ocount/2)
+  {
+  ocount = re->top_backref * 2 + 2;
+  match_block.offset_vector = (pcre_malloc)(ocount * sizeof(int));
+  if (match_block.offset_vector == NULL) return PCRE_ERROR_NOMEMORY;
+  #ifdef DEBUG
+  printf("Got memory to hold back references\n");
+  #endif
+  }
+else match_block.offset_vector = offsets;
+
+match_block.offset_end = ocount;
+match_block.offset_overflow = FALSE;
+
+/* Compute the minimum number of offsets that we need to reset each time. Doing
+this makes a huge difference to execution time when there aren't many brackets
+in the pattern. */
+
+resetcount = 2 + re->top_bracket * 2;
+if (resetcount > offsetcount) resetcount = ocount;
+
+/* If MULTILINE is set at exec time but was not set at compile time, and the
+anchored flag is set, we must re-check because a setting provoked by ^ in the
+pattern is not right in multi-line mode. Calling is_anchored() again here does
+the right check, because multiline is now set. If it now yields FALSE, the
+expression must have had ^ starting some of its branches. Check to see if
+that is true for *all* branches, and if so, set the startline flag. */
+
+if (match_block. multiline && anchored && (re->options & PCRE_MULTILINE) == 0 &&
+    !is_anchored(re->code, match_block.multiline))
+  {
+  anchored = FALSE;
+  if (is_startline(re->code)) startline = TRUE;
+  }
+
+/* Set up the first character to match, if available. The first_char value is
+never set for an anchored regular expression, but the anchoring may be forced
+at run time, so we have to test for anchoring. The first char may be unset for
+an unanchored pattern, of course. If there's no first char and the pattern was
+studied, the may be a bitmap of possible first characters. However, we can
+use this only if the caseless state of the studying was correct. */
+
+if (!anchored)
+  {
+  if ((re->options & PCRE_FIRSTSET) != 0)
+    {
+    first_char = re->first_char;
+    if (match_block.caseless) first_char = pcre_lcc[first_char];
+    }
+  else
+    if (!startline && extra != NULL &&
+      (extra->options & PCRE_STUDY_MAPPED) != 0 &&
+      ((extra->options & PCRE_STUDY_CASELESS) != 0) == match_block.caseless)
+        start_bits = extra->start_bits;
+  }
+
+/* Loop for unanchored matches; for anchored regexps the loop runs just once. */
+
+do
+  {
+  register int *iptr = match_block.offset_vector;
+  register int *iend = iptr + resetcount;
+
+  /* Reset the maximum number of extractions we might see. */
+
+  while (iptr < iend) *iptr++ = -1;
+
+  /* Advance to a unique first char if possible */
+
+  if (first_char >= 0)
+    {
+    if (match_block.caseless)
+      while (start_match < end_subject && pcre_lcc[*start_match] != first_char)
+        start_match++;
+    else
+      while (start_match < end_subject && *start_match != first_char)
+        start_match++;
+    }
+
+  /* Or to just after \n for a multiline match if possible */
+
+  else if (startline)
+    {
+    if (start_match > match_block.start_subject)
+      {
+      while (start_match < end_subject && start_match[-1] != '\n')
+        start_match++;
+      }
+    }
+
+  /* Or to a non-unique first char */
+
+  else if (start_bits != NULL)
+    {
+    while (start_match < end_subject)
+      {
+      register int c = *start_match;
+      if ((start_bits[c/8] & (1 << (c&7))) == 0) start_match++; else break;
+      }
+    }
+
+  #ifdef DEBUG
+  printf(">>>> Match against: ");
+  pchars(start_match, end_subject - start_match, TRUE, &match_block);
+  printf("\n");
+  #endif
+
+  /* When a match occurs, substrings will be set for all internal extractions;
+  we just need to set up the whole thing as substring 0 before returning. If
+  there were too many extractions, set the return code to zero. In the case
+  where we had to get some local store to hold offsets for backreferences, copy
+  those back references that we can. In this case there need not be overflow
+  if certain parts of the pattern were not used.
+
+  Before starting the match, we have to set up a longjmp() target to enable
+  the "cut" operation to fail a match completely without backtracking. */
+
+  if (setjmp(match_block.fail_env) == 0 &&
+      match(start_match, re->code, 2, &match_block))
+    {
+    int rc;
+
+    if (ocount != offsetcount)
+      {
+      if (offsetcount >= 4)
+        {
+        memcpy(offsets + 2, match_block.offset_vector + 2,
+          (offsetcount - 2) * sizeof(int));
+        #ifdef DEBUG
+        printf("Copied offsets; freeing temporary memory\n");
+        #endif
+        }
+      if (match_block.end_offset_top > offsetcount)
+        match_block.offset_overflow = TRUE;
+
+      #ifdef DEBUG
+      printf("Freeing temporary memory\n");
+      #endif
+
+      (pcre_free)(match_block.offset_vector);
+      }
+
+    rc = match_block.offset_overflow? 0 : match_block.end_offset_top/2;
+
+    if (match_block.offset_end < 2) rc = 0; else
+      {
+      offsets[0] = start_match - match_block.start_subject;
+      offsets[1] = match_block.end_match_ptr - match_block.start_subject;
+      }
+
+    #ifdef DEBUG
+    printf(">>>> returning %d\n", rc);
+    #endif
+    return rc;
+    }
+  }
+while (!anchored &&
+       match_block.errorcode == PCRE_ERROR_NOMATCH &&
+       start_match++ < end_subject);
+
+#ifdef DEBUG
+printf(">>>> returning %d\n", match_block.errorcode);
+#endif
+
+return match_block.errorcode;
+}
+
+/* End of pcre.c */
diff --git a/pcre.h b/pcre.h
new file mode 100644
index 0000000..777a94f
--- /dev/null
+++ b/pcre.h
@@ -0,0 +1,57 @@
+/*************************************************
+*       Perl-Compatible Regular Expressions      *
+*************************************************/
+
+/* Copyright (c) 1997 University of Cambridge */
+
+#ifndef _PCRE_H
+#define _PCRE_H
+
+/* Have to include stdlib.h in order to ensure that size_t is defined;
+it is needed here for malloc. */
+
+#include <stdlib.h>
+
+/* Options */
+
+#define PCRE_CASELESS        0x0001
+#define PCRE_EXTENDED        0x0002
+#define PCRE_ANCHORED        0x0004
+#define PCRE_MULTILINE       0x0008
+#define PCRE_DOTALL          0x0010
+#define PCRE_DOLLAR_ENDONLY  0x0020
+#define PCRE_EXTRA           0x0040
+#define PCRE_NOTBOL          0x0080
+#define PCRE_NOTEOL          0x0100
+
+/* Exec-time error codes */
+
+#define PCRE_ERROR_NOMATCH        (-1)
+#define PCRE_ERROR_BADREF         (-2)
+#define PCRE_ERROR_NULL           (-3)
+#define PCRE_ERROR_BADOPTION      (-4)
+#define PCRE_ERROR_BADMAGIC       (-5)
+#define PCRE_ERROR_UNKNOWN_NODE   (-6)
+#define PCRE_ERROR_NOMEMORY       (-7)
+
+/* Types */
+
+typedef void pcre;
+typedef void pcre_extra;
+
+/* Store get and free functions. These can be set to alternative malloc/free
+functions if required. */
+
+extern void *(*pcre_malloc)(size_t);
+extern void  (*pcre_free)(void *);
+
+/* Functions */
+
+extern pcre *pcre_compile(const char *, int, char **, int *);
+extern int pcre_exec(const pcre *, const pcre_extra *, const char *,
+  int, int, int *, int);
+extern int pcre_info(const pcre *, int *, int *);
+extern pcre_extra *pcre_study(const pcre *, int, char **);
+extern char *pcre_version(void);
+
+#endif /* End of pcre.h */
diff --git a/pcreposix.3 b/pcreposix.3
new file mode 100644
index 0000000..2c907e7
--- /dev/null
+++ b/pcreposix.3
@@ -0,0 +1,135 @@
+.TH PCRE 3
+.SH NAME
+pcreposix - POSIX API for Perl-compatible regular expressions.
+.SH SYNOPSIS
+.B #include <pcreposix.h>
+.PP
+.SM
+.br
+.B int regcomp(regex_t *\fIpreg\fR, const char *\fIpattern\fR,
+.ti +5n
+.B int \fIcflags\fR);
+.PP
+.br
+.B int regexec(regex_t *\fIpreg\fR, const char *\fIstring\fR,
+.ti +5n
+.B size_t \fInmatch\fR, regmatch_t \fIpmatch\fR[], int \fIeflags\fR);
+.PP
+.br
+.B size_t regerror(int \fIerrcode\fR, const regex_t *\fIpreg\fR,
+.ti +5n
+.B char *\fIerrbuf\fR, size_t \fIerrbuf_size\fR);
+.PP
+.br
+.B void regfree(regex_t *\fIpreg\fR);
+
+
+.SH DESCRIPTION
+This set of functions provides a POSIX-style API to the PCRE regular expression
+package. See \fBpcre (3)\fR for a description of the native API, which contains
+additional functionality. The functions described here are just wrapper
+functions that ultimately call the native API.
+
+As I am pretty ignorant about POSIX, these functions must be considered as
+experimental. I have implemented only those option bits that can be reasonably
+mapped to PCRE native options. Other POSIX options are not even defined. It may
+be that it is useful to define, but ignore, other options. Feedback from more
+knowledgeable folk may cause this kind of detail to change.
+
+When PCRE is called via these functions, it is only the API that is POSIX-like
+in style. The syntax and semantics of the regular expressions themselves are
+still those of Perl, subject to the setting of various PCRE options, as
+described below.
+
+The header for these functions is supplied as \fBpcreposix.h\fR to avoid any
+potential clash with other POSIX libraries. It can, of course, be renamed or
+aliased as \fBregex.h\fR, which is the "correct" name. It provides two
+structure types, \fIregex_t\fR for compiled internal forms, and
+\fIregmatch_t\fR for returning captured substrings. It also defines some
+constants whose names start with "REG_"; these are used for setting options and
+identifying error codes.
+
+
+.SH COMPILING A PATTERN
+
+The function \fBregcomp()\fR is called to compile a pattern into an
+internal form. The pattern is a C string terminated by a binary zero, and
+is passed in the argument \fIpattern\fR. The \fIpreg\fR argument is a pointer
+to a regex_t structure which is used as a base for storing information about
+the compiled expression.
+
+The argument \fIcflags\fR is either zero, or contains one or more of the bits
+defined by the following macros:
+
+  REG_ICASE
+
+The PCRE_CASELESS option is set when the expression is passed for compilation
+to the native function.
+
+  REG_NEWLINE
+
+The PCRE_MULTILINE option is set when the expression is passed for compilation
+to the native function.
+
+The yield of \fBregcomp()\fR is zero on success, and non-zero otherwise. The
+\fIpreg\fR structure is filled in on success, and one member of the structure
+is publicized: \fIre_nsub\fR contains the number of capturing subpatterns in
+the regular expression. Various error codes are defined in the header file.
+
+
+.SH MATCHING A PATTERN
+The function \fBregexec()\fR is called to match a pre-compiled pattern
+\fIpreg\fR against a given \fIstring\fR, which is terminated by a zero byte,
+subject to the options in \fIeflags\fR. These can be:
+
+  REG_NOTBOL
+
+The PCRE_NOTBOL option is set when calling the underlying PCRE matching
+function.
+
+  REG_NOTEOL
+
+The PCRE_NOTEOL option is set when calling the underlying PCRE matching
+function.
+
+The portion of the string that was matched, and also any captured substrings,
+are returned via the \fIpmatch\fR argument, which points to an array of
+\fInmatch\fR structures of type \fIregmatch_t\fR, containing the members
+\fIrm_so\fR and \fIrm_eo\fR. These contain the offset to the first character of
+each substring and the offset to the first character after the end of each
+substring, respectively. The 0th element of the vector relates to the entire
+portion of \fIstring\fR that was matched; subsequent elements relate to the
+capturing subpatterns of the regular expression. Unused entries in the array
+have both structure members set to -1.
+
+A successful match yields a zero return; various error codes are defined in the
+header file, of which REG_NOMATCH is the "expected" failure code.
+
+
+.SH ERROR MESSAGES
+The \fBregerror()\fR function maps a non-zero errorcode from either
+\fBregcomp\fR or \fBregexec\fR to a printable message. If \fIpreg\fR is not
+NULL, the error should have arisen from the use of that structure. A message
+terminated by a binary zero is placed in \fIerrbuf\fR. The length of the
+message, including the zero, is limited to \fIerrbuf_size\fR. The yield of the
+function is the size of buffer needed to hold the whole message.
+
+
+.SH STORAGE
+Compiling a regular expression causes memory to be allocated and associated
+with the \fIpreg\fR structure. The function \fBregfree()\fR frees all such
+memory, after which \fIpreg\fR may no longer be used as a compiled expression.
+
+
+.SH AUTHOR
+Philip Hazel <ph10@cam.ac.uk>
+.br
+University Computing Service,
+.br
+New Museums Site,
+.br
+Cambridge CB2 3QG, England.
+.br
+Phone: +44 1223 334714
+
+Copyright (c) 1997 University of Cambridge.
diff --git a/pcreposix.c b/pcreposix.c
new file mode 100644
index 0000000..1fbd9ac
--- /dev/null
+++ b/pcreposix.c
@@ -0,0 +1,246 @@
+/*************************************************
+*      Perl-Compatible Regular Expressions       *
+*************************************************/
+
+/*
+This is a library of functions to support regular expressions whose syntax
+and semantics are as close as possible to those of the Perl 5 language. See
+the file Tech.Notes for some information on the internals.
+
+This module is a wrapper that provides a POSIX API to the underlying PCRE
+functions.
+
+Written by: Philip Hazel <ph10@cam.ac.uk>
+
+           Copyright (c) 1997 University of Cambridge
+
+-----------------------------------------------------------------------------
+Permission is granted to anyone to use this software for any purpose on any
+computer system, and to redistribute it freely, subject to the following
+restrictions:
+
+1. This software is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+
+2. The origin of this software must not be misrepresented, either by
+   explicit claim or by omission.
+
+3. Altered versions must be plainly marked as such, and must not be
+   misrepresented as being the original software.
+-----------------------------------------------------------------------------
+*/
+
+#include "internal.h"
+#include "pcreposix.h"
+#include "stdlib.h"
+
+
+
+/* Corresponding tables of PCRE error messages and POSIX error codes. */
+
+static char *estring[] = {
+  ERR1,  ERR2,  ERR3,  ERR4,  ERR5,  ERR6,  ERR7,  ERR8,  ERR9,  ERR10,
+  ERR11, ERR12, ERR13, ERR14, ERR15, ERR16, ERR17, ERR18, ERR19, ERR20,
+  ERR21, ERR22, ERR23 };
+
+static int eint[] = {
+  REG_EESCAPE, /* "\\ at end of pattern" */
+  REG_EESCAPE, /* "\\c at end of pattern" */
+  REG_EESCAPE, /* "unrecognized character follows \\" */
+  REG_BADBR,   /* "numbers out of order in {} quantifier" */
+  REG_BADBR,   /* "number too big in {} quantifier" */
+  REG_EBRACK,  /* "missing terminating ] for character class" */
+  REG_ECTYPE,  /* "invalid escape sequence in character class" */
+  REG_ERANGE,  /* "range out of order in character class" */
+  REG_BADRPT,  /* "nothing to repeat" */
+  REG_BADRPT,  /* "operand of unlimited repeat could match the empty string" */
+  REG_ASSERT,  /* "internal error: unexpected repeat" */
+  REG_BADPAT,  /* "unrecognized character after (?" */
+  REG_ESIZE,   /* "too many capturing parenthesized sub-patterns" */
+  REG_EPAREN,  /* "missing )" */
+  REG_ESUBREG, /* "back reference to non-existent subpattern" */
+  REG_INVARG,  /* "erroffset passed as NULL" */
+  REG_INVARG,  /* "unknown option bit(s) set" */
+  REG_EPAREN,  /* "missing ) after comment" */
+  REG_ESIZE,   /* "too many sets of parentheses" */
+  REG_ESIZE,   /* "regular expression too large" */
+  REG_ESPACE,  /* "failed to get memory" */
+  REG_EPAREN,  /* "unmatched brackets" */
+  REG_ASSERT   /* "internal error: code overflow" */
+};
+
+/* Table of texts corresponding to POSIX error codes */
+
+static char *pstring[] = {
+  "",                                /* Dummy for value 0 */
+  "internal error",                  /* REG_ASSERT */
+  "invalid repeat counts in {}",     /* BADBR      */
+  "pattern error",                   /* BADPAT     */
+  "? * + invalid",                   /* BADRPT     */
+  "unbalanced {}",                   /* EBRACE     */
+  "unbalanced []",                   /* EBRACK     */
+  "collation error - not relevant",  /* ECOLLATE   */
+  "bad class",                       /* ECTYPE     */
+  "bad escape sequence",             /* EESCAPE    */
+  "empty expression",                /* EMPTY      */
+  "unbalanced ()",                   /* EPAREN     */
+  "bad range inside []",             /* ERANGE     */
+  "expression too big",              /* ESIZE      */
+  "failed to get memory",            /* ESPACE     */
+  "bad back reference",              /* ESUBREG    */
+  "bad argument",                    /* INVARG     */
+  "match failed"                     /* NOMATCH    */
+};
+
+
+
+
+/*************************************************
+*          Translate PCRE text code to int       *
+*************************************************/
+
+/* PCRE compile-time errors are given as strings defined as macros. We can just
+look them up in a table to turn them into POSIX-style error codes. */
+
+static int
+pcre_posix_error_code(const char *s)
+{
+int i;
+for (i = 0; i < sizeof(estring)/sizeof(char *); i++)
+  if (strcmp(s, estring[i]) == 0) return eint[i];
+return REG_ASSERT;
+}
+
+
+
+/*************************************************
+*          Translate error code to string        *
+*************************************************/
+
+size_t
+regerror(int errcode, const regex_t *preg, char *errbuf, size_t errbuf_size)
+{
+char *message, *addmessage;
+int length, adlength;
+
+message = (errcode >= sizeof(pstring)/sizeof(char *))?
+  "unknown error code" : pstring[errcode];
+
+length = (int)strlen(message) + 1;
+
+if (preg != NULL && (int)preg->re_erroffset != -1)
+  {
+  addmessage = " at offset ";
+  adlength = (int)strlen(addmessage) + 6;
+  }
+else adlength = 0;
+
+if (errbuf_size > 0)
+  {
+  if (adlength > 0 && errbuf_size >= length + adlength)
+    sprintf(errbuf, "%s%s%-6d", message, addmessage, preg->re_erroffset);
+  else
+    {
+    strncpy(errbuf, message, errbuf_size - 1);
+    errbuf[errbuf_size-1] = 0;
+    }
+  }
+
+return length + adlength;
+}
+
+
+
+
+/*************************************************
+*           Free store held by a regex           *
+*************************************************/
+
+void
+regfree(regex_t *preg)
+{
+(pcre_free)(preg->re_pcre);
+}
+
+
+
+
+/*************************************************
+*            Compile a regular expression        *
+*************************************************/
+
+/*
+Arguments:
+  preg        points to a structure for recording the compiled expression
+  pattern     the pattern to compile
+  cflags      compilation flags
+
+Returns:      0 on success
+              various non-zero codes on failure
+*/
+
+int
+regcomp(regex_t *preg, const char *pattern, int cflags)
+{
+char *errorptr;
+int erroffset;
+int options = 0;
+
+if ((cflags & REG_ICASE) != 0) options |= PCRE_CASELESS;
+if ((cflags & REG_NEWLINE) != 0) options |= PCRE_MULTILINE;
+
+preg->re_pcre = pcre_compile(pattern, options, &errorptr, &erroffset);
+preg->re_erroffset = erroffset;
+
+if (preg->re_pcre == NULL) return pcre_posix_error_code(errorptr);
+
+preg->re_nsub = pcre_info(preg->re_pcre, NULL, NULL);
+return 0;
+}
+
+
+
+
+/*************************************************
+*              Match a regular expression        *
+*************************************************/
+
+int
+regexec(regex_t *preg, const char *string, size_t nmatch,
+  regmatch_t pmatch[], int eflags)
+{
+int rc;
+int options = 0;
+
+if ((eflags & REG_NOTBOL) != 0) options |= PCRE_NOTBOL;
+if ((eflags & REG_NOTEOL) != 0) options |= PCRE_NOTEOL;
+
+preg->re_erroffset = -1;   /* Only has meaning after compile */
+
+rc = pcre_exec(preg->re_pcre, NULL, string, (int)strlen(string), options,
+  (int *)pmatch, nmatch * 2);
+
+if (rc == 0) return 0;    /* All pmatch were filled in */
+
+if (rc > 0)
+  {
+  int i;
+  for (i = rc; i < nmatch; i++) pmatch[i].rm_so = pmatch[i].rm_eo = -1;
+  return 0;
+  }
+
+else switch(rc)
+  {
+  case PCRE_ERROR_NOMATCH: return REG_NOMATCH;
+  case PCRE_ERROR_BADREF: return REG_ESUBREG;
+  case PCRE_ERROR_NULL: return REG_INVARG;
+  case PCRE_ERROR_BADOPTION: return REG_INVARG;
+  case PCRE_ERROR_BADMAGIC: return REG_INVARG;
+  case PCRE_ERROR_UNKNOWN_NODE: return REG_ASSERT;
+  case PCRE_ERROR_NOMEMORY: return REG_ESPACE;
+  default: return REG_ASSERT;
+  }
+}
+
+/* End of pcreposix.c */
diff --git a/pcreposix.h b/pcreposix.h
new file mode 100644
index 0000000..1d0f16a
--- /dev/null
+++ b/pcreposix.h
@@ -0,0 +1,72 @@
+/*************************************************
+*       Perl-Compatible Regular Expressions      *
+*************************************************/
+
+/* Copyright (c) 1997 University of Cambridge */
+
+#ifndef _PCREPOSIX_H
+#define _PCREPOSIX_H
+
+/* This is the header for the POSIX wrapper interface to the PCRE Perl-
+Compatible Regular Expression library. It defines the things POSIX says should
+be there. I hope. */
+
+/* Have to include stdlib.h in order to ensure that size_t is defined. */
+
+#include <stdlib.h>
+
+/* Options defined by POSIX. */
+
+#define REG_ICASE     0x01
+#define REG_NEWLINE   0x02
+#define REG_NOTBOL    0x04
+#define REG_NOTEOL    0x08
+
+/* Error values. Not all these are relevant or used by the wrapper. */
+
+enum {
+  REG_ASSERT = 1,  /* internal error ? */
+  REG_BADBR,       /* invalid repeat counts in {} */
+  REG_BADPAT,      /* pattern error */
+  REG_BADRPT,      /* ? * + invalid */
+  REG_EBRACE,      /* unbalanced {} */
+  REG_EBRACK,      /* unbalanced [] */
+  REG_ECOLLATE,    /* collation error - not relevant */
+  REG_ECTYPE,      /* bad class */
+  REG_EESCAPE,     /* bad escape sequence */
+  REG_EMPTY,       /* empty expression */
+  REG_EPAREN,      /* unbalanced () */
+  REG_ERANGE,      /* bad range inside [] */
+  REG_ESIZE,       /* expression too big */
+  REG_ESPACE,      /* failed to get memory */
+  REG_ESUBREG,     /* bad back reference */
+  REG_INVARG,      /* bad argument */
+  REG_NOMATCH      /* match failed */
+};
+
+
+/* The structure representing a compiled regular expression. */
+
+typedef struct {
+  void *re_pcre;
+  size_t re_nsub;
+  size_t re_erroffset;
+} regex_t;
+
+/* The structure in which a captured offset is returned. */
+
+typedef int regoff_t;
+
+typedef struct {
+  regoff_t rm_so;
+  regoff_t rm_eo;
+} regmatch_t;
+
+/* The functions */
+
+extern int regcomp(regex_t *, const char *, int);
+extern int regexec(regex_t *, const char *, size_t, regmatch_t *, int);
+extern size_t regerror(int, const regex_t *, char *, size_t);
+extern void regfree(regex_t *);
+
+#endif /* End of pcreposix.h */
diff --git a/pcretest.c b/pcretest.c
new file mode 100644
index 0000000..6b558b2
--- /dev/null
+++ b/pcretest.c
@@ -0,0 +1,771 @@
+/*************************************************
+*             PCRE testing program               *
+*************************************************/
+
+#include <ctype.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <time.h>
+
+/* Use the internal info for displaying the results of pcre_study(). */
+
+#include "internal.h"
+#include "pcreposix.h"
+
+#ifndef CLOCKS_PER_SEC
+#ifdef CLK_TCK
+#define CLOCKS_PER_SEC CLK_TCK
+#else
+#define CLOCKS_PER_SEC 100
+#endif
+#endif
+
+
+static FILE *outfile;
+static int log_store = 0;
+
+
+
+/* Debugging function to print the internal form of the regex. This is the same
+code as contained in pcre.c under the DEBUG macro. */
+
+static char *OP_names[] = { "End", "\\A", "\\B", "\\b", "\\D", "\\d",
+  "\\S", "\\s", "\\W", "\\w", "Cut", "\\Z", "^", "$", "Any", "chars",
+  "not",
+  "*", "*?", "+", "+?", "?", "??", "{", "{", "{",
+  "*", "*?", "+", "+?", "?", "??", "{", "{", "{",
+  "*", "*?", "+", "+?", "?", "??", "{", "{", "{",
+  "*", "*?", "+", "+?", "?", "??", "{", "{",
+  "class", "Ref",
+  "Alt", "Ket", "KetRmax", "KetRmin", "Assert", "Assert not", "Once",
+  "Brazero", "Braminzero", "Bra"
+};
+
+
+static void print_internals(pcre *re)
+{
+unsigned char *code = ((real_pcre *)re)->code;
+
+printf("------------------------------------------------------------------\n");
+
+for(;;)
+  {
+  int c;
+  int charlength;
+
+  printf("%3d ", code - ((real_pcre *)re)->code);
+
+  if (*code >= OP_BRA)
+    {
+    printf("%3d Bra %d", (code[1] << 8) + code[2], *code - OP_BRA);
+    code += 2;
+    }
+
+  else switch(*code)
+    {
+    case OP_END:
+    printf("    %s\n", OP_names[*code]);
+    printf("------------------------------------------------------------------\n");
+    return;
+
+    case OP_CHARS:
+    charlength = *(++code);
+    printf("%3d ", charlength);
+    while (charlength-- > 0)
+      if (isprint(c = *(++code))) printf("%c", c); else printf("\\x%02x", c);
+    break;
+
+    case OP_KETRMAX:
+    case OP_KETRMIN:
+    case OP_ALT:
+    case OP_KET:
+    case OP_ASSERT:
+    case OP_ASSERT_NOT:
+    case OP_ONCE:
+    printf("%3d %s", (code[1] << 8) + code[2], OP_names[*code]);
+    code += 2;
+    break;
+
+    case OP_STAR:
+    case OP_MINSTAR:
+    case OP_PLUS:
+    case OP_MINPLUS:
+    case OP_QUERY:
+    case OP_MINQUERY:
+    case OP_TYPESTAR:
+    case OP_TYPEMINSTAR:
+    case OP_TYPEPLUS:
+    case OP_TYPEMINPLUS:
+    case OP_TYPEQUERY:
+    case OP_TYPEMINQUERY:
+    if (*code >= OP_TYPESTAR)
+      printf("    %s", OP_names[code[1]]);
+    else if (isprint(c = code[1])) printf("    %c", c);
+      else printf("    \\x%02x", c);
+    printf("%s", OP_names[*code++]);
+    break;
+
+    case OP_EXACT:
+    case OP_UPTO:
+    case OP_MINUPTO:
+    if (isprint(c = code[3])) printf("    %c{", c);
+      else printf("    \\x%02x{", c);
+    if (*code != OP_EXACT) printf(",");
+    printf("%d}", (code[1] << 8) + code[2]);
+    if (*code == OP_MINUPTO) printf("?");
+    code += 3;
+    break;
+
+    case OP_TYPEEXACT:
+    case OP_TYPEUPTO:
+    case OP_TYPEMINUPTO:
+    printf("    %s{", OP_names[code[3]]);
+    if (*code != OP_TYPEEXACT) printf(",");
+    printf("%d}", (code[1] << 8) + code[2]);
+    if (*code == OP_TYPEMINUPTO) printf("?");
+    code += 3;
+    break;
+
+    case OP_NOT:
+    if (isprint(c = *(++code))) printf("    [^%c]", c);
+      else printf("    [^\\x%02x]", c);
+    break;
+
+    case OP_NOTSTAR:
+    case OP_NOTMINSTAR:
+    case OP_NOTPLUS:
+    case OP_NOTMINPLUS:
+    case OP_NOTQUERY:
+    case OP_NOTMINQUERY:
+    if (isprint(c = code[1])) printf("    [^%c]", c);
+      else printf("    [^\\x%02x]", c);
+    printf("%s", OP_names[*code++]);
+    break;
+
+    case OP_NOTEXACT:
+    case OP_NOTUPTO:
+    case OP_NOTMINUPTO:
+    if (isprint(c = code[3])) printf("    [^%c]{", c);
+      else printf("    [^\\x%02x]{", c);
+    if (*code != OP_NOTEXACT) printf(",");
+    printf("%d}", (code[1] << 8) + code[2]);
+    if (*code == OP_NOTMINUPTO) printf("?");
+    code += 3;
+    break;
+
+    case OP_REF:
+    printf("    \\%d", *(++code));
+    break;
+
+    case OP_CLASS:
+      {
+      int i, min, max;
+
+      code++;
+      printf("    [");
+
+      for (i = 0; i < 256; i++)
+        {
+        if ((code[i/8] & (1 << (i&7))) != 0)
+          {
+          int j;
+          for (j = i+1; j < 256; j++)
+            if ((code[j/8] & (1 << (j&7))) == 0) break;
+          if (i == '-' || i == ']') printf("\\");
+          if (isprint(i)) printf("%c", i); else printf("\\x%02x", i);
+          if (--j > i)
+            {
+            printf("-");
+            if (j == '-' || j == ']') printf("\\");
+            if (isprint(j)) printf("%c", j); else printf("\\x%02x", j);
+            }
+          i = j;
+          }
+        }
+      printf("]");
+      code += 32;
+
+      switch(*code)
+        {
+        case OP_CRSTAR:
+        case OP_CRMINSTAR:
+        case OP_CRPLUS:
+        case OP_CRMINPLUS:
+        case OP_CRQUERY:
+        case OP_CRMINQUERY:
+        printf("%s", OP_names[*code]);
+        break;
+
+        case OP_CRRANGE:
+        case OP_CRMINRANGE:
+        min = (code[1] << 8) + code[2];
+        max = (code[3] << 8) + code[4];
+        if (max == 0) printf("{%d,}", min);
+        else printf("{%d,%d}", min, max);
+        if (*code == OP_CRMINRANGE) printf("?");
+        code += 4;
+        break;
+
+        default:
+        code--;
+        }
+      }
+    break;
+
+    /* Anything else is just a one-node item */
+
+    default:
+    printf("    %s", OP_names[*code]);
+    break;
+    }
+
+  code++;
+  printf("\n");
+  }
+}
+
+
+
+/* Character string printing function. */
+
+static void pchars(unsigned char *p, int length)
+{
+int c;
+while (length-- > 0)
+  if (isprint(c = *(p++))) fprintf(outfile, "%c", c);
+    else fprintf(outfile, "\\x%02x", c);
+}
+
+
+
+/* Alternative malloc function, to test functionality and show the size of the
+compiled re. */
+
+static void *new_malloc(size_t size)
+{
+if (log_store) fprintf(outfile, "Store size request: %d\n", (int)size);
+return malloc(size);
+}
+
+
+
+/* Read lines from named file or stdin and write to named file or stdout; lines
+consist of a regular expression, in delimiters and optionally followed by
+options, followed by a set of test data, terminated by an empty line. */
+
+int main(int argc, char **argv)
+{
+FILE *infile = stdin;
+int options = 0;
+int study_options = 0;
+int op = 1;
+int timeit = 0;
+int showinfo = 0;
+int posix = 0;
+int debug = 0;
+unsigned char buffer[30000];
+unsigned char dbuffer[1024];
+
+/* Static so that new_malloc can use it. */
+
+outfile = stdout;
+
+/* Scan options */
+
+while (argc > 1 && argv[op][0] == '-')
+  {
+  if (strcmp(argv[op], "-s") == 0) log_store = 1;
+  else if (strcmp(argv[op], "-t") == 0) timeit = 1;
+  else if (strcmp(argv[op], "-i") == 0) showinfo = 1;
+  else if (strcmp(argv[op], "-d") == 0) showinfo = debug = 1;
+  else if (strcmp(argv[op], "-p") == 0) posix = 1;
+  else
+    {
+    printf("*** Unknown option %s\n", argv[op]);
+    return 1;
+    }
+  op++;
+  argc--;
+  }
+
+/* Sort out the input and output files */
+
+if (argc > 1)
+  {
+  infile = fopen(argv[op], "r");
+  if (infile == NULL)
+    {
+    printf("** Failed to open %s\n", argv[op]);
+    return 1;
+    }
+  }
+
+if (argc > 2)
+  {
+  outfile = fopen(argv[op+1], "w");
+  if (outfile == NULL)
+    {
+    printf("** Failed to open %s\n", argv[op+1]);
+    return 1;
+    }
+  }
+
+/* Set alternative malloc function */
+
+pcre_malloc = new_malloc;
+
+/* Heading line, then prompt for first re if stdin */
+
+fprintf(outfile, "Testing Perl-Compatible Regular Expressions\n");
+fprintf(outfile, "PCRE version %s\n\n", pcre_version());
+
+/* Main loop */
+
+for (;;)
+  {
+  pcre *re = NULL;
+  pcre_extra *extra = NULL;
+  regex_t preg;
+  char *error;
+  unsigned char *p, *pp;
+  int do_study = 0;
+  int do_debug = 0;
+  int do_posix = 0;
+  int erroroffset, len, delimiter;
+
+  if (infile == stdin) printf("  re> ");
+  if (fgets((char *)buffer, sizeof(buffer), infile) == NULL) break;
+  if (infile != stdin) fprintf(outfile, (char *)buffer);
+
+  p = buffer;
+  while (isspace(*p)) p++;
+  if (*p == 0) continue;
+
+  /* Get the delimiter and seek the end of the pattern; if is isn't
+  complete, read more. */
+
+  delimiter = *p++;
+
+  if (isalnum(delimiter))
+    {
+    fprintf(outfile, "** Delimiter must not be alphameric\n");
+    goto SKIP_DATA;
+    }
+
+  pp = p;
+
+  for(;;)
+    {
+    while (*pp != 0 && *pp != delimiter) pp++;
+    if (*pp != 0) break;
+
+    len = sizeof(buffer) - (pp - buffer);
+    if (len < 256)
+      {
+      fprintf(outfile, "** Expression too long - missing delimiter?\n");
+      goto SKIP_DATA;
+      }
+
+    if (infile == stdin) printf("    > ");
+    if (fgets((char *)pp, len, infile) == NULL)
+      {
+      fprintf(outfile, "** Unexpected EOF\n");
+      goto END_OFF;
+      }
+    if (infile != stdin) fprintf(outfile, (char *)pp);
+    }
+
+  /* Terminate the pattern at the delimiter */
+
+  *pp++ = 0;
+
+  /* Look for options after final delimiter */
+
+  options = 0;
+  study_options = 0;
+  while (*pp != 0)
+    {
+    switch (*pp++)
+      {
+      case 'i': options |= PCRE_CASELESS; break;
+      case 'm': options |= PCRE_MULTILINE; break;
+      case 's': options |= PCRE_DOTALL; break;
+      case 'x': options |= PCRE_EXTENDED; break;
+      case 'A': options |= PCRE_ANCHORED; break;
+      case 'D': do_debug = 1; break;
+      case 'E': options |= PCRE_DOLLAR_ENDONLY; break;
+      case 'P': do_posix = 1; break;
+      case 'S': do_study = 1; break;
+      case 'I': study_options |= PCRE_CASELESS; break;
+      case 'X': options |= PCRE_EXTRA; break;
+      case '\n': case ' ': break;
+      default:
+      fprintf(outfile, "** Unknown option '%c'\n", pp[-1]);
+      goto SKIP_DATA;
+      }
+    }
+
+  /* Handle compiing via the POSIX interface, which doesn't support the
+  timing, showing, or debugging options. */
+
+  if (posix || do_posix)
+    {
+    int rc;
+    int cflags = 0;
+    if ((options & PCRE_CASELESS) != 0) cflags |= REG_ICASE;
+    if ((options & PCRE_MULTILINE) != 0) cflags |= REG_NEWLINE;
+    rc = regcomp(&preg, (char *)p, cflags);
+
+    /* Compilation failed; go back for another re, skipping to blank line
+    if non-interactive. */
+
+    if (rc != 0)
+      {
+      (void)regerror(rc, &preg, (char *)buffer, sizeof(buffer));
+      fprintf(outfile, "Failed: POSIX code %d: %s\n", rc, buffer);
+      goto SKIP_DATA;
+      }
+    }
+
+  /* Handle compiling via the native interface */
+
+  else
+    {
+    if (timeit)
+      {
+      register int i;
+      clock_t time_taken;
+      clock_t start_time = clock();
+      for (i = 0; i < 4000; i++)
+        {
+        re = pcre_compile((char *)p, options, &error, &erroroffset);
+        if (re != NULL) free(re);
+        }
+      time_taken = clock() - start_time;
+      fprintf(outfile, "Compile time %.2f milliseconds\n",
+        ((double)time_taken)/(4 * CLOCKS_PER_SEC));
+      }
+
+    re = pcre_compile((char *)p, options, &error, &erroroffset);
+
+    /* Compilation failed; go back for another re, skipping to blank line
+    if non-interactive. */
+
+    if (re == NULL)
+      {
+      fprintf(outfile, "Failed: %s at offset %d\n", error, erroroffset);
+      SKIP_DATA:
+      if (infile != stdin)
+        {
+        for (;;)
+          {
+          if (fgets((char *)buffer, sizeof(buffer), infile) == NULL)
+            goto END_OFF;
+          len = (int)strlen((char *)buffer);
+          while (len > 0 && isspace(buffer[len-1])) len--;
+          if (len == 0) break;
+          }
+        fprintf(outfile, "\n");
+        }
+      continue;
+      }
+
+    /* Compilation succeeded; print data if required */
+
+    if (showinfo || do_debug)
+      {
+      int first_char, count;
+
+      if (debug || do_debug) print_internals(re);
+
+      count = pcre_info(re, &options, &first_char);
+      if (count < 0) fprintf(outfile,
+        "Error %d while reading info\n", count);
+      else
+        {
+        fprintf(outfile, "Identifying subpattern count = %d\n", count);
+        if (options == 0) fprintf(outfile, "No options\n");
+          else fprintf(outfile, "Options:%s%s%s%s%s%s%s\n",
+            ((options & PCRE_ANCHORED) != 0)? " anchored" : "",
+            ((options & PCRE_CASELESS) != 0)? " caseless" : "",
+            ((options & PCRE_EXTENDED) != 0)? " extended" : "",
+            ((options & PCRE_MULTILINE) != 0)? " multiline" : "",
+            ((options & PCRE_DOTALL) != 0)? " dotall" : "",
+            ((options & PCRE_DOLLAR_ENDONLY) != 0)? " dollar_endonly" : "",
+            ((options & PCRE_EXTRA) != 0)? " extra" : "");
+        if (first_char == -1)
+          {
+          fprintf(outfile, "First char at start or follows \\n\n");
+          }
+        else if (first_char < 0)
+          {
+          fprintf(outfile, "No first char\n");
+          }
+        else
+          {
+          if (isprint(first_char))
+            fprintf(outfile, "First char = \'%c\'\n", first_char);
+          else
+            fprintf(outfile, "First char = %d\n", first_char);
+          }
+        }
+      }
+
+    /* If /S was present, study the regexp to generate additional info to
+    help with the matching. */
+
+    if (do_study)
+      {
+      if (timeit)
+        {
+        register int i;
+        clock_t time_taken;
+        clock_t start_time = clock();
+        for (i = 0; i < 4000; i++)
+          extra = pcre_study(re, study_options, &error);
+        time_taken = clock() - start_time;
+        if (extra != NULL) free(extra);
+        fprintf(outfile, "  Study time %.2f milliseconds\n",
+          ((double)time_taken)/(4 * CLOCKS_PER_SEC));
+        }
+
+      extra = pcre_study(re, study_options, &error);
+      if (error != NULL)
+        fprintf(outfile, "Failed to study: %s\n", error);
+      else if (extra == NULL)
+        fprintf(outfile, "Study returned NULL\n");
+
+      /* This looks at internal information. A bit kludgy to do it this
+      way, but it is useful for testing. */
+
+      else if (showinfo || do_debug)
+        {
+        real_pcre_extra *xx = (real_pcre_extra *)extra;
+        if ((xx->options & PCRE_STUDY_MAPPED) == 0)
+          fprintf(outfile, "No starting character set\n");
+        else
+          {
+          int i;
+          int c = 24;
+          fprintf(outfile, "Starting character set: ");
+          for (i = 0; i < 256; i++)
+            {
+            if ((xx->start_bits[i/8] & (1<<(i%8))) != 0)
+              {
+              if (c > 75)
+                {
+                fprintf(outfile, "\n  ");
+                c = 2;
+                }
+              if (isprint(i) && i != ' ')
+                {
+                fprintf(outfile, "%c ", i);
+                c += 2;
+                }
+              else
+                {
+                fprintf(outfile, "\\x%02x ", i);
+                c += 5;
+                }
+              }
+            }
+          fprintf(outfile, "\n");
+          }
+        }
+      }
+    }
+
+  /* Read data lines and test them */
+
+  for (;;)
+    {
+    unsigned char *pp;
+    int count, c;
+    int offsets[30];
+    int size_offsets = sizeof(offsets)/sizeof(int);
+
+    options = 0;
+
+    if (infile == stdin) printf("  data> ");
+    if (fgets((char *)buffer, sizeof(buffer), infile) == NULL) goto END_OFF;
+    if (infile != stdin) fprintf(outfile, (char *)buffer);
+
+    len = (int)strlen((char *)buffer);
+    while (len > 0 && isspace(buffer[len-1])) len--;
+    buffer[len] = 0;
+    if (len == 0) break;
+
+    p = buffer;
+    while (isspace(*p)) p++;
+
+    pp = dbuffer;
+    while ((c = *p++) != 0)
+      {
+      int i = 0;
+      int n = 0;
+      if (c == '\\') switch ((c = *p++))
+        {
+        case 'a': c =    7; break;
+        case 'b': c = '\b'; break;
+        case 'e': c =   27; break;
+        case 'f': c = '\f'; break;
+        case 'n': c = '\n'; break;
+        case 'r': c = '\r'; break;
+        case 't': c = '\t'; break;
+        case 'v': c = '\v'; break;
+
+        case '0': case '1': case '2': case '3':
+        case '4': case '5': case '6': case '7':
+        c -= '0';
+        while (i++ < 2 && isdigit(*p) && *p != '8' && *p != '9')
+          c = c * 8 + *p++ - '0';
+        break;
+
+        case 'x':
+        c = 0;
+        while (i++ < 2 && isxdigit(*p))
+          {
+          c = c * 16 + tolower(*p) - ((isdigit(*p))? '0' : 'W');
+          p++;
+          }
+        break;
+
+        case 0:   /* Allows for an empty line */
+        p--;
+        continue;
+
+        case 'A':  /* Option setting */
+        options |= PCRE_ANCHORED;
+        continue;
+
+        case 'B':
+        options |= PCRE_NOTBOL;
+        continue;
+
+        case 'E':
+        options |= PCRE_DOLLAR_ENDONLY;
+        continue;
+
+        case 'I':
+        options |= PCRE_CASELESS;
+        continue;
+
+        case 'M':
+        options |= PCRE_MULTILINE;
+        continue;
+
+        case 'S':
+        options |= PCRE_DOTALL;
+        continue;
+
+        case 'O':
+        while(isdigit(*p)) n = n * 10 + *p++ - '0';
+        if (n <= sizeof(offsets)/sizeof(int)) size_offsets = n;
+        continue;
+
+        case 'Z':
+        options |= PCRE_NOTEOL;
+        continue;
+        }
+      *pp++ = c;
+      }
+    *pp = 0;
+    len = pp - dbuffer;
+
+    /* Handle matching via the POSIX interface, which does not
+    support timing. */
+
+    if (posix || do_posix)
+      {
+      int rc;
+      int eflags = 0;
+      regmatch_t pmatch[30];
+      if ((options & PCRE_NOTBOL) != 0) eflags |= REG_NOTBOL;
+      if ((options & PCRE_NOTEOL) != 0) eflags |= REG_NOTEOL;
+
+      rc = regexec(&preg, (char *)dbuffer, sizeof(pmatch)/sizeof(regmatch_t),
+        pmatch, eflags);
+
+      if (rc != 0)
+        {
+        (void)regerror(rc, &preg, (char *)buffer, sizeof(buffer));
+        fprintf(outfile, "No match: POSIX code %d: %s\n", rc, buffer);
+        }
+      else
+        {
+        int i;
+        for (i = 0; i < sizeof(pmatch)/sizeof(regmatch_t); i++)
+          {
+          if (pmatch[i].rm_so >= 0)
+            {
+            fprintf(outfile, "%2d: ", i);
+            pchars(dbuffer + pmatch[i].rm_so,
+              pmatch[i].rm_eo - pmatch[i].rm_so);
+            fprintf(outfile, "\n");
+            }
+          }
+        }
+      }
+
+    /* Handle matching via the native interface */
+
+    else
+      {
+      if (timeit)
+        {
+        register int i;
+        clock_t time_taken;
+        clock_t start_time = clock();
+        for (i = 0; i < 4000; i++)
+          count = pcre_exec(re, extra, (char *)dbuffer, len, options, offsets,
+            size_offsets);
+        time_taken = clock() - start_time;
+        fprintf(outfile, "Execute time %.2f milliseconds\n",
+          ((double)time_taken)/(4 * CLOCKS_PER_SEC));
+        }
+
+      count = pcre_exec(re, extra, (char *)dbuffer, len, options, offsets,
+        size_offsets);
+
+      if (count == 0)
+        {
+        fprintf(outfile, "Matched, but too many substrings\n");
+        count = size_offsets/2;
+        }
+
+      if (count >= 0)
+        {
+        int i;
+        count *= 2;
+        for (i = 0; i < count; i += 2)
+          {
+          if (offsets[i] < 0)
+            fprintf(outfile, "%2d: <unset>\n", i/2);
+          else
+            {
+            fprintf(outfile, "%2d: ", i/2);
+            pchars(dbuffer + offsets[i], offsets[i+1] - offsets[i]);
+            fprintf(outfile, "\n");
+            }
+          }
+        }
+      else
+        {
+        if (count == -1) fprintf(outfile, "No match\n");
+          else fprintf(outfile, "Error %d\n", count);
+        }
+      }
+    }
+
+  if (posix || do_posix) regfree(&preg);
+  if (re != NULL) free(re);
+  if (extra != NULL) free(extra);
+  }
+
+END_OFF:
+fprintf(outfile, "\n");
+return 0;
+}
+
+/* End */
diff --git a/perltest b/perltest
new file mode 100755
index 0000000..7c2114b
--- /dev/null
+++ b/perltest
@@ -0,0 +1,143 @@
+#! /usr/bin/perl
+
+# Program for testing regular expressions with perl to check that PCRE handles
+# them the same.
+
+
+# Function for turning a string into a string of printing chars
+
+sub pchars {
+my($t) = "";
+
+foreach $c (split(//, @_[0]))
+  {
+  if (ord $c >= 32 && ord $c < 127) { $t .= $c; }
+    else { $t .= sprintf("\\x%02x", ord $c); }
+  }
+$t;
+}
+
+
+
+# Read lines from named file or stdin and write to named file or stdout; lines
+# consist of a regular expression, in delimiters and optionally followed by
+# options, followed by a set of test data, terminated by an empty line.
+
+# Sort out the input and output files
+
+if (@ARGV > 0)
+  {
+  open(INFILE, "<$ARGV[0]") || die "Failed to open $ARGV[0]\n";
+  $infile = "INFILE";
+  }
+else { $infile = "STDIN"; }
+
+if (@ARGV > 1)
+  {
+  open(OUTFILE, ">$ARGV[1]") || die "Failed to open $ARGV[1]\n";
+  $outfile = "OUTFILE";
+  }
+else { $outfile = "STDOUT"; }
+
+printf($outfile "Perl Regular Expressions\n\n");
+
+# Main loop
+
+NEXT_RE:
+for (;;)
+  {
+  printf "  re> " if $infile eq "STDIN";
+  last if ! ($_ = <$infile>);
+  printf $outfile "$_" if $infile ne "STDIN";
+  next if ($_ eq "");
+
+  $pattern = $_;
+
+  $delimiter = substr($_, 0, 1);
+  while ($pattern !~ /^\s*(.).*\1/s)
+    {
+    printf "    > " if $infile eq "STDIN";
+    last if ! ($_ = <$infile>);
+    printf $outfile "$_" if $infile ne "STDIN";
+    $pattern .= $_;
+    }
+
+   chomp($pattern);
+   $pattern =~ s/\s+$//;
+
+  # Check that the pattern is valid
+
+  eval "\$_ =~ ${pattern}";
+  if ($@)
+    {
+    printf $outfile "Error: $@\n";
+    next NEXT_RE;
+    }
+
+  # Read data lines and test them
+
+  for (;;)
+    {
+    printf "data> " if $infile eq "STDIN";
+    last NEXT_RE if ! ($_ = <$infile>);
+    chomp;
+    printf $outfile "$_\n" if $infile ne "STDIN";
+
+    s/\s+$//;
+    s/^\s+//;
+
+    last if ($_ eq "");
+
+    $_ = eval "\"$_\"";   # To get escapes processed
+
+    $ok = 0;
+    eval "if (\$_ =~ ${pattern}) {" .
+         "\$z = \$&;" .
+         "\$a = \$1;" .
+         "\$b = \$2;" .
+         "\$c = \$3;" .
+         "\$d = \$4;" .
+         "\$e = \$5;" .
+         "\$f = \$6;" .
+         "\$g = \$7;" .
+         "\$h = \$8;" .
+         "\$i = \$9;" .
+         "\$j = \$10;" .
+         "\$k = \$11;" .
+         "\$l = \$12;" .
+         "\$m = \$13;" .
+         "\$n = \$14;" .
+         "\$o = \$15;" .
+         "\$p = \$16;" .
+         "\$ok = 1; }";
+
+    if ($@)
+      {
+      printf $outfile "Error: $@\n";
+      next NEXT_RE;
+      }
+    elsif (!$ok)
+      {
+      printf $outfile "No match\n";
+      }
+    else
+      {
+      @subs = ($z,$a,$b,$c,$d,$e,$f,$g,$h,$i,$j,$k,$l,$m,$n,$o,$p);
+      $last_printed = 0;
+      for ($i = 0; $i <= 17; $i++)
+        {
+        if ($i == 0 || defined $subs[$i])
+          {
+          while ($last_printed++ < $i-1)
+            { printf $outfile ("%2d: <unset>\n", $last_printed); }
+          printf $outfile ("%2d: %s\n", $i, &pchars($subs[$i]));
+          $last_printed = $i;
+          }
+        }
+      }
+    }
+  }
+
+printf $outfile "\n";
+
+# End
diff --git a/pgrep.1 b/pgrep.1
new file mode 100644
index 0000000..6df6775
--- /dev/null
+++ b/pgrep.1
@@ -0,0 +1,72 @@
+.TH PGREP 1
+.SH NAME
+pgrep - a grep with Perl-compatible regular expressions.
+.SH SYNOPSIS
+.B pgrep [-chilnsvx] pattern [file] ...
+
+
+.SH DESCRIPTION
+\fBpgrep\fR searches files for character patterns, in the same way as other
+grep commands do, but it uses the PCRE regular expression library to support
+patterns that are compatible with the regular expressions of Perl 5. See
+\fBpcre(3)\fR for a full description of syntax and semantics.
+
+If no files are specified, \fBpgrep\fR reads the standard input. By default,
+each line that matches the pattern is copied to the standard output, and if
+there is more than one file, the file name is printed before each line of
+output. However, there are options that can change how \fBpgrep\fR behaves.
+
+Lines are limited to BUFSIZ characters. BUFSIZ is defined in \fB<stdio.h>\fR.
+The newline character is removed from the end of each line before it is matched
+against the pattern.
+
+
+.SH OPTIONS
+.TP 10
+\fB-c\fR
+Do not print individual lines; instead just print a count of the number of
+lines that would otherwise have been printed. If several files are given, a
+count is printed for each of them.
+.TP
+\fB-h\fR
+Suppress printing of filenames when searching multiple files.
+.TP
+\fB-i\fR
+Ignore upper/lower case distinctions during comparisons.
+.TP
+\fB-l\fR
+Instead of printing lines from the files, just print the names of the files
+containing lines that would have been printed. Each file name is printed
+once, on a separate line.
+.TP
+\fB-n\fR
+Precede each line by its line number in the file.
+.TP
+\fB-s\fR
+Work silently, that is, display nothing except error messages.
+The exit status indicates whether any matches were found.
+.TP
+\fB-v\fR
+Invert the sense of the match, so that lines which do \fInot\fR match the
+pattern are now the ones that are found.
+.TP
+\fB-x\fR
+Force the pattern to be anchored (it must start matching at the beginning of
+the line) and in addition, require it to match the entire line. This is
+equivalent to having ^ and $ characters at the start and end of each
+alternative branch in the regular expression.
+
+
+.SH SEE ALSO
+\fBpcre(3)\fR, Perl 5 documentation
+
+
+.SH DIAGNOSTICS
+Exit status is 0 if any matches were found, 1 if no matches were found, and 2
+for syntax errors or inacessible files (even if matches were found).
+
+
+.SH AUTHOR
+Philip Hazel <ph10@cam.ac.uk>
+.br
+Copyright (c) 1997 University of Cambridge.
diff --git a/pgrep.c b/pgrep.c
new file mode 100644
index 0000000..ba78c2b
--- /dev/null
+++ b/pgrep.c
@@ -0,0 +1,220 @@
+/*************************************************
+*               PCRE grep program                *
+*************************************************/
+
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <errno.h>
+#include "pcre.h"
+
+
+#define FALSE 0
+#define TRUE 1
+
+typedef int BOOL;
+
+
+
+/*************************************************
+*               Global variables                 *
+*************************************************/
+
+static pcre *pattern;
+static pcre_extra *hints;
+
+static BOOL count_only = FALSE;
+static BOOL filenames_only = FALSE;
+static BOOL invert = FALSE;
+static BOOL number = FALSE;
+static BOOL silent = FALSE;
+static BOOL whole_lines = FALSE;
+
+
+
+#ifdef STRERROR_FROM_ERRLIST
+/*************************************************
+*     Provide strerror() for non-ANSI libraries  *
+*************************************************/
+
+/* Some old-fashioned systems still around (e.g. SunOS4) don't have strerror()
+in their libraries, but can provide the same facility by this simple
+alternative function. */
+
+extern int   sys_nerr;
+extern char *sys_errlist[];
+
+char *
+strerror(int n)
+{
+if (n < 0 || n >= sys_nerr) return "unknown error number";
+return sys_errlist[n];
+}
+#endif /* STRERROR_FROM_ERRLIST */
+
+
+
+/*************************************************
+*              Grep an individual file           *
+*************************************************/
+
+static int
+pgrep(FILE *in, char *name)
+{
+int rc = 1;
+int linenumber = 0;
+int count = 0;
+int offsets[2];
+char buffer[BUFSIZ];
+
+while (fgets(buffer, sizeof(buffer), in) != NULL)
+  {
+  BOOL match;
+  int length = (int)strlen(buffer);
+  if (length > 0 && buffer[length-1] == '\n') buffer[--length] = 0;
+  linenumber++;
+
+  match = pcre_exec(pattern, hints, buffer, length, 0, offsets, 2) >= 0;
+  if (match && whole_lines && offsets[1] != length) match = FALSE;
+
+  if (match != invert)
+    {
+    if (count_only) count++;
+
+    else if (filenames_only)
+      {
+      fprintf(stdout, "%s\n", (name == NULL)? "<stdin>" : name);
+      return 0;
+      }
+
+    else if (silent) return 0;
+
+    else
+      {
+      if (name != NULL) fprintf(stdout, "%s:", name);
+      if (number) fprintf(stdout, "%d:", linenumber);
+      fprintf(stdout, "%s\n", buffer);
+      }
+
+    rc = 0;
+    }
+  }
+
+if (count_only)
+  {
+  if (name != NULL) fprintf(stdout, "%s:", name);
+  fprintf(stdout, "%d\n", count);
+  }
+
+return rc;
+}
+
+
+
+
+/*************************************************
+*                Usage function                  *
+*************************************************/
+
+static int
+usage(int rc)
+{
+fprintf(stderr, "Usage: pgrep [-chilnsvx] pattern [file] ...\n");
+return rc;
+}
+
+
+
+
+/*************************************************
+*                Main program                    *
+*************************************************/
+
+int
+main(int argc, char **argv)
+{
+int i;
+int rc = 1;
+int options = 0;
+int errptr;
+char *error;
+BOOL filenames = TRUE;
+
+/* Process the options */
+
+for (i = 1; i < argc; i++)
+  {
+  char *s;
+  if (argv[i][0] != '-') break;
+  s = argv[i] + 1;
+  while (*s != 0)
+    {
+    switch (*s++)
+      {
+      case 'c': count_only = TRUE; break;
+      case 'h': filenames = FALSE; break;
+      case 'i': options |= PCRE_CASELESS; break;
+      case 'l': filenames_only = TRUE;
+      case 'n': number = TRUE; break;
+      case 's': silent = TRUE; break;
+      case 'v': invert = TRUE; break;
+      case 'x': whole_lines = TRUE; options |= PCRE_ANCHORED; break;
+      default:
+      fprintf(stderr, "pgrep: unknown option %c\n", s[-1]);
+      return usage(2);
+      }
+    }
+  }
+
+/* There must be at least a regexp argument */
+
+if (i >= argc) return usage(0);
+
+/* Compile the regular expression. */
+
+pattern = pcre_compile(argv[i++], options, &error, &errptr);
+if (pattern == NULL)
+  {
+  fprintf(stderr, "pgrep: error in regex at offset %d: %s\n", errptr, error);
+  return 2;
+  }
+
+/* Study the regular expression, as we will be running it may times */
+
+hints = pcre_study(pattern, 0, &error);
+if (error != NULL)
+  {
+  fprintf(stderr, "pgrep: error while studing regex: %s\n", error);
+  return 2;
+  }
+
+/* If there are no further arguments, do the business on stdin and exit */
+
+if (i >= argc) return pgrep(stdin, NULL);
+
+/* Otherwise, work through the remaining arguments as files. If there is only
+one, don't give its name on the output. */
+
+if (i == argc - 1) filenames = FALSE;
+if (filenames_only) filenames = TRUE;
+
+for (; i < argc; i++)
+  {
+  FILE *in = fopen(argv[i], "r");
+  if (in == NULL)
+    {
+    fprintf(stderr, "%s: failed to open: %s\n", argv[i], strerror(errno));
+    rc = 2;
+    }
+  else
+    {
+    int frc = pgrep(in, filenames? argv[i] : NULL);
+    if (frc == 0 && rc == 1) rc = 0;
+    fclose(in);
+    }
+  }
+
+return rc;
+}
+
+/* End */
diff --git a/study.c b/study.c
new file mode 100644
index 0000000..e1be917
--- /dev/null
+++ b/study.c
@@ -0,0 +1,337 @@
+/*************************************************
+*      Perl-Compatible Regular Expressions       *
+*************************************************/
+
+/*
+This is a library of functions to support regular expressions whose syntax
+and semantics are as close as possible to those of the Perl 5 language. See
+the file Tech.Notes for some information on the internals.
+
+Written by: Philip Hazel <ph10@cam.ac.uk>
+
+           Copyright (c) 1997 University of Cambridge
+
+-----------------------------------------------------------------------------
+Permission is granted to anyone to use this software for any purpose on any
+computer system, and to redistribute it freely, subject to the following
+restrictions:
+
+1. This software is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+
+2. The origin of this software must not be misrepresented, either by
+   explicit claim or by omission.
+
+3. Altered versions must be plainly marked as such, and must not be
+   misrepresented as being the original software.
+-----------------------------------------------------------------------------
+*/
+
+
+/* Include the internals header, which itself includes Standard C headers plus
+the external pcre header. */
+
+#include "internal.h"
+
+
+
+/*************************************************
+*          Create bitmap of starting chars       *
+*************************************************/
+
+/* This function scans a compiled unanchored expression and attempts to build a
+bitmap of the set of initial characters. If it can't, it returns FALSE. As time
+goes by, we may be able to get more clever at doing this.
+
+Arguments:
+  code         points to an expression
+  start_bits   points to a 32-byte table, initialized to 0
+
+Returns:       TRUE if table built, FALSE otherwise
+*/
+
+static BOOL
+set_start_bits(uschar *code, uschar *start_bits)
+{
+register int c;
+
+do
+  {
+  uschar *tcode = code + 3;
+  BOOL try_next = TRUE;
+
+  while (try_next)
+    {
+    try_next = FALSE;
+
+    if ((int)*tcode >= OP_BRA || *tcode == OP_ASSERT)
+      {
+      if (!set_start_bits(tcode, start_bits)) return FALSE;
+      }
+
+    else switch(*tcode)
+      {
+      default:
+      return FALSE;
+
+      /* BRAZERO does the bracket, but carries on. */
+
+      case OP_BRAZERO:
+      case OP_BRAMINZERO:
+      if (!set_start_bits(++tcode, start_bits)) return FALSE;
+      do tcode += (tcode[1] << 8) + tcode[2]; while (*tcode == OP_ALT);
+      tcode += 3;
+      try_next = TRUE;
+      break;
+
+      /* Single-char * or ? sets the bit and tries the next item */
+
+      case OP_STAR:
+      case OP_MINSTAR:
+      case OP_QUERY:
+      case OP_MINQUERY:
+      start_bits[tcode[1]/8] |= (1 << (tcode[1]&7));
+      tcode += 2;
+      try_next = TRUE;
+      break;
+
+      /* Single-char upto sets the bit and tries the next */
+
+      case OP_UPTO:
+      case OP_MINUPTO:
+      start_bits[tcode[3]/8] |= (1 << (tcode[3]&7));
+      tcode += 4;
+      try_next = TRUE;
+      break;
+
+      /* At least one single char sets the bit and stops */
+
+      case OP_EXACT:       /* Fall through */
+      tcode++;
+
+      case OP_CHARS:       /* Fall through */
+      tcode++;
+
+      case OP_PLUS:
+      case OP_MINPLUS:
+      start_bits[tcode[1]/8] |= (1 << (tcode[1]&7));
+      break;
+
+      /* Single character type sets the bits and stops */
+
+      case OP_NOT_DIGIT:
+      for (c = 0; c < 32; c++) start_bits[c] |= ~pcre_cbits[c+cbit_digit];
+      break;
+
+      case OP_DIGIT:
+      for (c = 0; c < 32; c++) start_bits[c] |= pcre_cbits[c+cbit_digit];
+      break;
+
+      case OP_NOT_WHITESPACE:
+      for (c = 0; c < 32; c++) start_bits[c] |= ~pcre_cbits[c+cbit_space];
+      break;
+
+      case OP_WHITESPACE:
+      for (c = 0; c < 32; c++) start_bits[c] |= pcre_cbits[c+cbit_space];
+      break;
+
+      case OP_NOT_WORDCHAR:
+      for (c = 0; c < 32; c++)
+        start_bits[c] |= ~(pcre_cbits[c] | pcre_cbits[c+cbit_word]);
+      break;
+
+      case OP_WORDCHAR:
+      for (c = 0; c < 32; c++)
+        start_bits[c] |= (pcre_cbits[c] | pcre_cbits[c+cbit_word]);
+      break;
+
+      /* One or more character type fudges the pointer and restarts, knowing
+      it will hit a single character type and stop there. */
+
+      case OP_TYPEPLUS:
+      case OP_TYPEMINPLUS:
+      tcode++;
+      try_next = TRUE;
+      break;
+
+      case OP_TYPEEXACT:
+      tcode += 3;
+      try_next = TRUE;
+      break;
+
+      /* Zero or more repeats of character types set the bits and then
+      try again. */
+
+      case OP_TYPEUPTO:
+      case OP_TYPEMINUPTO:
+      tcode += 2;               /* Fall through */
+
+      case OP_TYPESTAR:
+      case OP_TYPEMINSTAR:
+      case OP_TYPEQUERY:
+      case OP_TYPEMINQUERY:
+      switch(tcode[1])
+        {
+        case OP_NOT_DIGIT:
+        for (c = 0; c < 32; c++) start_bits[c] |= ~pcre_cbits[c+cbit_digit];
+        break;
+
+        case OP_DIGIT:
+        for (c = 0; c < 32; c++) start_bits[c] |= pcre_cbits[c+cbit_digit];
+        break;
+
+        case OP_NOT_WHITESPACE:
+        for (c = 0; c < 32; c++) start_bits[c] |= ~pcre_cbits[c+cbit_space];
+        break;
+
+        case OP_WHITESPACE:
+        for (c = 0; c < 32; c++) start_bits[c] |= pcre_cbits[c+cbit_space];
+        break;
+
+        case OP_NOT_WORDCHAR:
+        for (c = 0; c < 32; c++)
+          start_bits[c] |= ~(pcre_cbits[c] | pcre_cbits[c+cbit_word]);
+        break;
+
+        case OP_WORDCHAR:
+        for (c = 0; c < 32; c++)
+          start_bits[c] |= (pcre_cbits[c] | pcre_cbits[c+cbit_word]);
+        break;
+        }
+
+      tcode += 2;
+      try_next = TRUE;
+      break;
+
+      /* Character class: set the bits and either carry on or not,
+      according to the repeat count. */
+
+      case OP_CLASS:
+        {
+        tcode++;
+        for (c = 0; c < 32; c++) start_bits[c] |= tcode[c];
+        tcode += 32;
+        switch (*tcode)
+          {
+          case OP_CRSTAR:
+          case OP_CRMINSTAR:
+          case OP_CRQUERY:
+          case OP_CRMINQUERY:
+          tcode++;
+          try_next = TRUE;
+          break;
+
+          case OP_CRRANGE:
+          case OP_CRMINRANGE:
+          if (((tcode[1] << 8) + tcode[2]) == 0)
+            {
+            tcode += 5;
+            try_next = TRUE;
+            }
+          break;
+          }
+        }
+      break; /* End of class handling */
+
+      }      /* End of switch */
+    }        /* End of try_next loop */
+
+  code += (code[1] << 8) + code[2];   /* Advance to next branch */
+  }
+while (*code == OP_ALT);
+return TRUE;
+}
+
+
+
+/*************************************************
+*          Study a compiled expression           *
+*************************************************/
+
+/* This function is handed a compiled expression that it must study to produce
+information that will speed up the matching. It returns a pcre_extra block
+which then gets handed back to pcre_exec().
+
+Arguments:
+  re        points to the compiled expression
+  options   contains option bits
+  errorptr  points to where to place error messages;
+            set NULL unless error
+
+Returns:    pointer to a pcre_extra block,
+            NULL on error or if no optimization possible
+*/
+
+pcre_extra *
+pcre_study(const pcre *external_re, int options, char **errorptr)
+{
+BOOL caseless;
+uschar start_bits[32];
+real_pcre_extra *extra;
+real_pcre *re = (real_pcre *)external_re;
+
+*errorptr = NULL;
+
+if (re == NULL || re->magic_number != MAGIC_NUMBER)
+  {
+  *errorptr = "argument is not a compiled regular expression";
+  return NULL;
+  }
+
+if ((options & ~PUBLIC_STUDY_OPTIONS) != 0)
+  {
+  *errorptr = "unknown or incorrect option bit(s) set";
+  return NULL;
+  }
+
+/* Caseless can either be from the compiled regex or from options. */
+
+caseless = ((re->options | options) & PCRE_CASELESS) != 0;
+
+/* For an anchored pattern, or an unchored pattern that has a first char, or a
+multiline pattern that matches only at "line starts", no further processing at
+present. */
+
+if ((re->options & (PCRE_ANCHORED|PCRE_FIRSTSET|PCRE_STARTLINE)) != 0)
+  return NULL;
+
+/* See if we can find a fixed set of initial characters for the pattern. */
+
+memset(start_bits, 0, 32 * sizeof(uschar));
+if (!set_start_bits(re->code, start_bits)) return NULL;
+
+/* If this studying is caseless, scan the created bit map and duplicate the
+bits for any letters. */
+
+if (caseless)
+  {
+  register int c;
+  for (c = 0; c < 256; c++)
+    {
+    if ((start_bits[c/8] & (1 << (c&7))) != 0 &&
+        (pcre_ctypes[c] & ctype_letter) != 0)
+      {
+      int d = pcre_fcc[c];
+      start_bits[d/8] |= (1 << (d&7));
+      }
+    }
+  }
+
+/* Get an "extra" block and put the information therein. */
+
+extra = (real_pcre_extra *)(pcre_malloc)(sizeof(real_pcre_extra));
+
+if (extra == NULL)
+  {
+  *errorptr = "failed to get memory";
+  return NULL;
+  }
+
+extra->options = PCRE_STUDY_MAPPED | (caseless? PCRE_STUDY_CASELESS : 0);
+memcpy(extra->start_bits, start_bits, sizeof(start_bits));
+
+return (pcre_extra *)extra;
+}
+
+/* End of study.c */
diff --git a/testinput b/testinput
new file mode 100644
index 0000000..0c00e7f
--- /dev/null
+++ b/testinput
@@ -0,0 +1,1551 @@
+/the quick brown fox/
+    the quick brown fox
+    The quick brown FOX
+    What do you know about the quick brown fox?
+    What do you know about THE QUICK BROWN FOX?
+
+/The quick brown fox/i
+    the quick brown fox
+    The quick brown FOX
+    What do you know about the quick brown fox?
+    What do you know about THE QUICK BROWN FOX?
+
+/abcd\t\n\r\f\a\e\071\x3b\$\\\?caxyz/
+    abcd\t\n\r\f\a\e9;\$\\?caxyz
+
+/a*abc?xyz+pqr{3}ab{2,}xy{4,5}pq{0,6}AB{0,}zz/
+    abxyzpqrrrabbxyyyypqAzz
+    abxyzpqrrrabbxyyyypqAzz
+    aabxyzpqrrrabbxyyyypqAzz
+    aaabxyzpqrrrabbxyyyypqAzz
+    aaaabxyzpqrrrabbxyyyypqAzz
+    abcxyzpqrrrabbxyyyypqAzz
+    aabcxyzpqrrrabbxyyyypqAzz
+    aaabcxyzpqrrrabbxyyyypAzz
+    aaabcxyzpqrrrabbxyyyypqAzz
+    aaabcxyzpqrrrabbxyyyypqqAzz
+    aaabcxyzpqrrrabbxyyyypqqqAzz
+    aaabcxyzpqrrrabbxyyyypqqqqAzz
+    aaabcxyzpqrrrabbxyyyypqqqqqAzz
+    aaabcxyzpqrrrabbxyyyypqqqqqqAzz
+    aaaabcxyzpqrrrabbxyyyypqAzz
+    abxyzzpqrrrabbxyyyypqAzz
+    aabxyzzzpqrrrabbxyyyypqAzz
+    aaabxyzzzzpqrrrabbxyyyypqAzz
+    aaaabxyzzzzpqrrrabbxyyyypqAzz
+    abcxyzzpqrrrabbxyyyypqAzz
+    aabcxyzzzpqrrrabbxyyyypqAzz
+    aaabcxyzzzzpqrrrabbxyyyypqAzz
+    aaaabcxyzzzzpqrrrabbxyyyypqAzz
+    aaaabcxyzzzzpqrrrabbbxyyyypqAzz
+    aaaabcxyzzzzpqrrrabbbxyyyyypqAzz
+    aaabcxyzpqrrrabbxyyyypABzz
+    aaabcxyzpqrrrabbxyyyypABBzz
+    >>>aaabxyzpqrrrabbxyyyypqAzz
+    >aaaabxyzpqrrrabbxyyyypqAzz
+    >>>>abcxyzpqrrrabbxyyyypqAzz
+    *** Failers
+    abxyzpqrrabbxyyyypqAzz
+    abxyzpqrrrrabbxyyyypqAzz
+    abxyzpqrrrabxyyyypqAzz
+    aaaabcxyzzzzpqrrrabbbxyyyyyypqAzz
+    aaaabcxyzzzzpqrrrabbbxyyypqAzz
+    aaabcxyzpqrrrabbxyyyypqqqqqqqAzz
+
+/^(abc){1,2}zz/
+    abczz
+    abcabczz
+    *** Failers
+    zz
+    abcabcabczz
+    >>abczz
+
+/^(b+?|a){1,2}?c/
+    bc
+    bbc
+    bbbc
+    bac
+    bbac
+    aac
+    abbbbbbbbbbbc
+    bbbbbbbbbbbac
+    *** Failers
+    aaac
+    abbbbbbbbbbbac
+
+/^(b+|a){1,2}c/
+    bc
+    bbc
+    bbbc
+    bac
+    bbac
+    aac
+    abbbbbbbbbbbc
+    bbbbbbbbbbbac
+    *** Failers
+    aaac
+    abbbbbbbbbbbac
+
+/^(b+|a){1,2}?bc/
+    bbc
+
+/^(b*|ba){1,2}?bc/
+    babc
+    bbabc
+    bababc
+    *** Failers
+    bababbc
+    babababc
+
+/^(ba|b*){1,2}?bc/
+    babc
+    bbabc
+    bababc
+    *** Failers
+    bababbc
+    babababc
+
+/^\ca\cA\c[\c{\c:/
+    \x01\x01\e;z
+
+/^[ab\]cde]/
+    athing
+    bthing
+    ]thing
+    cthing
+    dthing
+    ething
+    *** Failers
+    fthing
+    [thing
+    \\thing
+
+/^[]cde]/
+    ]thing
+    cthing
+    dthing
+    ething
+    *** Failers
+    athing
+    fthing
+
+/^[^ab\]cde]/
+    fthing
+    [thing
+    \\thing
+    *** Failers
+    athing
+    bthing
+    ]thing
+    cthing
+    dthing
+    ething
+
+/^[^]cde]/
+    athing
+    fthing
+    *** Failers
+    ]thing
+    cthing
+    dthing
+    ething
+
+/^\�/
+    �
+
+/^ÿ/
+    ÿ
+
+/^[0-9]+$/
+    0
+    1
+    2
+    3
+    4
+    5
+    6
+    7
+    8
+    9
+    10
+    100
+    *** Failers
+    abc
+
+/^.*nter/
+    enter
+    inter
+    uponter
+
+/^xxx[0-9]+$/
+    xxx0
+    xxx1234
+    *** Failers
+    xxx
+
+/^.+[0-9][0-9][0-9]$/
+    x123
+    xx123
+    123456
+    *** Failers
+    123
+    x1234
+
+/^.+?[0-9][0-9][0-9]$/
+    x123
+    xx123
+    123456
+    *** Failers
+    123
+    x1234
+
+/^([^!]+)!(.+)=apquxz\.ixr\.zzz\.ac\.uk$/
+    abc!pqr=apquxz.ixr.zzz.ac.uk
+    *** Failers
+    !pqr=apquxz.ixr.zzz.ac.uk
+    abc!=apquxz.ixr.zzz.ac.uk
+    abc!pqr=apquxz:ixr.zzz.ac.uk
+    abc!pqr=apquxz.ixr.zzz.ac.ukk
+
+/:/
+    Well, we need a colon: somewhere
+    *** Fail if we don't
+
+/([\da-f:]+)$/i
+    0abc
+    abc
+    fed
+    E
+    ::
+    5f03:12C0::932e
+    fed def
+    Any old stuff
+    *** Failers
+    0zzz
+    gzzz
+    fed\x20
+    Any old rubbish
+
+/^.*\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})$/
+    .1.2.3
+    A.12.123.0
+    *** Failers
+    .1.2.3333
+    1.2.3
+    1234.2.3
+
+/^(\d+)\s+IN\s+SOA\s+(\S+)\s+(\S+)\s*\(\s*$/
+    1 IN SOA non-sp1 non-sp2(
+    1    IN    SOA    non-sp1    non-sp2   (
+    *** Failers
+    1IN SOA non-sp1 non-sp2(
+
+/^[a-zA-Z\d][a-zA-Z\d\-]*(\.[a-zA-Z\d][a-zA-z\d\-]*)*\.$/
+    a.
+    Z.
+    2.
+    ab-c.pq-r.
+    sxk.zzz.ac.uk.
+    x-.y-.
+    *** Failers
+    -abc.peq.
+
+/^\*\.[a-z]([a-z\-\d]*[a-z\d]+)?(\.[a-z]([a-z\-\d]*[a-z\d]+)?)*$/
+    *.a
+    *.b0-a
+    *.c3-b.c
+    *.c-a.b-c
+    *** Failers
+    *.0
+    *.a-
+    *.a-b.c-
+    *.c-a.0-c
+
+/^(?=ab(de))(abd)(e)/
+    abde
+
+/^(?!(ab)de|x)(abd)(f)/
+    abdf
+
+/^(?=(ab(cd)))(ab)/
+    abcd
+
+/^[\da-f](\.[\da-f])*$/i
+    a.b.c.d
+    A.B.C.D
+    a.b.c.1.2.3.C
+
+/^\".*\"\s*(;.*)?$/
+    \"1234\"
+    \"abcd\" ;
+    \"\" ; rhubarb
+    *** Failers
+    \"1234\" : things
+
+/^$/
+    \
+    *** Failers
+
+/   ^    a   (?# begins with a)  b\sc (?# then b c) $ (?# then end)/x
+    ab c
+    *** Failers
+    abc
+    ab cde
+
+/(?x)   ^    a   (?# begins with a)  b\sc (?# then b c) $ (?# then end)/
+    ab c
+    *** Failers
+    abc
+    ab cde
+
+/^   a\ b[c ]d       $/x
+    a bcd
+    a b d
+    *** Failers
+    abcd
+    ab d
+
+/^(a(b(c)))(d(e(f)))(h(i(j)))(k(l(m)))$/
+    abcdefhijklm
+
+/^(?:a(b(c)))(?:d(e(f)))(?:h(i(j)))(?:k(l(m)))$/
+    abcdefhijklm
+
+/^[\w][\W][\s][\S][\d][\D][\b][\n][\c]][\022]/
+    a+ Z0+\x08\n\x1d\x12
+
+/^[.^$|()*+?{,}]+/
+    .^\$(*+)|{?,?}
+
+/^a*\w/
+    z
+    az
+    aaaz
+    a
+    aa
+    aaaa
+    a+
+    aa+
+
+/^a*?\w/
+    z
+    az
+    aaaz
+    a
+    aa
+    aaaa
+    a+
+    aa+
+
+/^a+\w/
+    az
+    aaaz
+    aa
+    aaaa
+    aa+
+
+/^a+?\w/
+    az
+    aaaz
+    aa
+    aaaa
+    aa+
+
+/^\d{8}\w{2,}/
+    1234567890
+    12345678ab
+    12345678__
+    *** Failers
+    1234567
+
+/^[aeiou\d]{4,5}$/
+    uoie
+    1234
+    12345
+    aaaaa
+    *** Failers
+    123456
+
+/^[aeiou\d]{4,5}?/
+    uoie
+    1234
+    12345
+    aaaaa
+    123456
+
+/\A(abc|def)=(\1){2,3}\Z/
+    abc=abcabc
+    def=defdefdef
+    *** Failers
+    abc=defdef
+
+/^(a)(b)(c)(d)(e)(f)(g)(h)(i)(j)(k)\11*(\3\4)\1(?#)2$/
+    abcdefghijkcda2
+    abcdefghijkkkkcda2
+
+/(cat(a(ract|tonic)|erpillar)) \1()2(3)/
+    cataract cataract23
+    catatonic catatonic23
+    caterpillar caterpillar23
+
+
+/^From +([^ ]+) +[a-zA-Z][a-zA-Z][a-zA-Z] +[a-zA-Z][a-zA-Z][a-zA-Z] +[0-9]?[0-9] +[0-9][0-9]:[0-9][0-9]/
+    From abcd  Mon Sep 01 12:33:02 1997
+
+/^From\s+\S+\s+([a-zA-Z]{3}\s+){2}\d{1,2}\s+\d\d:\d\d/
+    From abcd  Mon Sep 01 12:33:02 1997
+    From abcd  Mon Sep  1 12:33:02 1997
+    *** Failers
+    From abcd  Sep 01 12:33:02 1997
+
+/^12.34/s
+    12\n34
+    12\r34
+
+/\w+(?=\t)/
+    the quick brown\t fox
+
+/foo(?!bar)(.*)/
+    foobar is foolish see?
+
+/(?:(?!foo)...|^.{0,2})bar(.*)/
+    foobar crowbar etc
+    barrel
+    2barrel
+    A barrel
+
+/^(\D*)(?=\d)(?!123)/
+    abc456
+    *** Failers
+    abc123
+
+/^1234(?# test newlines
+  inside)/
+    1234
+
+/^1234 #comment in extended re
+  /x
+    1234
+
+/#rhubarb
+  abcd/x
+    abcd
+
+/^abcd#rhubarb/x
+    abcd
+
+/^(a)\1{2,3}(.)/
+    aaab
+    aaaab
+    aaaaab
+    aaaaaab
+
+/(?!^)abc/
+    the abc
+    *** Failers
+    abc
+
+/(?=^)abc/
+    abc
+    *** Failers
+    the abc
+
+/^[ab]{1,3}(ab*|b)/
+    aabbbbb
+
+/^[ab]{1,3}?(ab*|b)/
+    aabbbbb
+
+/^[ab]{1,3}?(ab*?|b)/
+    aabbbbb
+
+/^[ab]{1,3}(ab*?|b)/
+    aabbbbb
+
+/  (?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*                          # optional leading comment
+(?:    (?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|
+" (?:                      # opening quote...
+[^\\\x80-\xff\n\015"]                #   Anything except backslash and quote
+|                     #    or
+\\ [^\x80-\xff]           #   Escaped something (something != CR)
+)* "  # closing quote
+)                    # initial word
+(?:  (?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*  \.  (?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*   (?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|
+" (?:                      # opening quote...
+[^\\\x80-\xff\n\015"]                #   Anything except backslash and quote
+|                     #    or
+\\ [^\x80-\xff]           #   Escaped something (something != CR)
+)* "  # closing quote
+)  )* # further okay, if led by a period
+(?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*  @  (?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*    (?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|   \[                         # [
+(?: [^\\\x80-\xff\n\015\[\]] |  \\ [^\x80-\xff]  )*    #    stuff
+\]                        #           ]
+)                           # initial subdomain
+(?:                                  #
+(?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*  \.                        # if led by a period...
+(?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*   (?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|   \[                         # [
+(?: [^\\\x80-\xff\n\015\[\]] |  \\ [^\x80-\xff]  )*    #    stuff
+\]                        #           ]
+)                     #   ...further okay
+)*
+# address
+|                     #  or
+(?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|
+" (?:                      # opening quote...
+[^\\\x80-\xff\n\015"]                #   Anything except backslash and quote
+|                     #    or
+\\ [^\x80-\xff]           #   Escaped something (something != CR)
+)* "  # closing quote
+)             # one word, optionally followed by....
+(?:
+[^()<>@,;:".\\\[\]\x80-\xff\000-\010\012-\037]  |  # atom and space parts, or...
+\(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)       |  # comments, or...
+
+" (?:                      # opening quote...
+[^\\\x80-\xff\n\015"]                #   Anything except backslash and quote
+|                     #    or
+\\ [^\x80-\xff]           #   Escaped something (something != CR)
+)* "  # closing quote
+# quoted strings
+)*
+<  (?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*                     # leading <
+(?:  @  (?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*    (?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|   \[                         # [
+(?: [^\\\x80-\xff\n\015\[\]] |  \\ [^\x80-\xff]  )*    #    stuff
+\]                        #           ]
+)                           # initial subdomain
+(?:                                  #
+(?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*  \.                        # if led by a period...
+(?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*   (?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|   \[                         # [
+(?: [^\\\x80-\xff\n\015\[\]] |  \\ [^\x80-\xff]  )*    #    stuff
+\]                        #           ]
+)                     #   ...further okay
+)*
+
+(?:  (?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*  ,  (?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*  @  (?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*    (?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|   \[                         # [
+(?: [^\\\x80-\xff\n\015\[\]] |  \\ [^\x80-\xff]  )*    #    stuff
+\]                        #           ]
+)                           # initial subdomain
+(?:                                  #
+(?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*  \.                        # if led by a period...
+(?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*   (?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|   \[                         # [
+(?: [^\\\x80-\xff\n\015\[\]] |  \\ [^\x80-\xff]  )*    #    stuff
+\]                        #           ]
+)                     #   ...further okay
+)*
+)* # further okay, if led by comma
+:                                # closing colon
+(?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*  )? #       optional route
+(?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|
+" (?:                      # opening quote...
+[^\\\x80-\xff\n\015"]                #   Anything except backslash and quote
+|                     #    or
+\\ [^\x80-\xff]           #   Escaped something (something != CR)
+)* "  # closing quote
+)                    # initial word
+(?:  (?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*  \.  (?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*   (?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|
+" (?:                      # opening quote...
+[^\\\x80-\xff\n\015"]                #   Anything except backslash and quote
+|                     #    or
+\\ [^\x80-\xff]           #   Escaped something (something != CR)
+)* "  # closing quote
+)  )* # further okay, if led by a period
+(?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*  @  (?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*    (?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|   \[                         # [
+(?: [^\\\x80-\xff\n\015\[\]] |  \\ [^\x80-\xff]  )*    #    stuff
+\]                        #           ]
+)                           # initial subdomain
+(?:                                  #
+(?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*  \.                        # if led by a period...
+(?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*   (?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|   \[                         # [
+(?: [^\\\x80-\xff\n\015\[\]] |  \\ [^\x80-\xff]  )*    #    stuff
+\]                        #           ]
+)                     #   ...further okay
+)*
+#       address spec
+(?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*  > #                  trailing >
+# name and address
+)  (?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*                       # optional trailing comment
+/x
+    Alan Other <user\@dom.ain>
+    <user\@dom.ain>
+    user\@dom.ain
+    \"A. Other\" <user.1234\@dom.ain> (a comment)
+    A. Other <user.1234\@dom.ain> (a comment)
+    \"/s=user/ou=host/o=place/prmd=uu.yy/admd= /c=gb/\"\@x400-re.lay
+    A missing angle <user\@some.where
+    *** Failers
+    The quick brown fox
+
+/[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+# optional leading comment
+(?:
+(?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+# Atom
+|                       #  or
+"                                     # "
+[^\\\x80-\xff\n\015"] *                            #   normal
+(?:  \\ [^\x80-\xff]  [^\\\x80-\xff\n\015"] * )*        #   ( special normal* )*
+"                                     #        "
+# Quoted string
+)
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+(?:
+\.
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+(?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+# Atom
+|                       #  or
+"                                     # "
+[^\\\x80-\xff\n\015"] *                            #   normal
+(?:  \\ [^\x80-\xff]  [^\\\x80-\xff\n\015"] * )*        #   ( special normal* )*
+"                                     #        "
+# Quoted string
+)
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+# additional words
+)*
+@
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+(?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|
+\[                            # [
+(?: [^\\\x80-\xff\n\015\[\]] |  \\ [^\x80-\xff]  )*     #    stuff
+\]                           #           ]
+)
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+# optional trailing comments
+(?:
+\.
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+(?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|
+\[                            # [
+(?: [^\\\x80-\xff\n\015\[\]] |  \\ [^\x80-\xff]  )*     #    stuff
+\]                           #           ]
+)
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+# optional trailing comments
+)*
+# address
+|                             #  or
+(?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+# Atom
+|                       #  or
+"                                     # "
+[^\\\x80-\xff\n\015"] *                            #   normal
+(?:  \\ [^\x80-\xff]  [^\\\x80-\xff\n\015"] * )*        #   ( special normal* )*
+"                                     #        "
+# Quoted string
+)
+# leading word
+[^()<>@,;:".\\\[\]\x80-\xff\000-\010\012-\037] *               # "normal" atoms and or spaces
+(?:
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+|
+"                                     # "
+[^\\\x80-\xff\n\015"] *                            #   normal
+(?:  \\ [^\x80-\xff]  [^\\\x80-\xff\n\015"] * )*        #   ( special normal* )*
+"                                     #        "
+) # "special" comment or quoted string
+[^()<>@,;:".\\\[\]\x80-\xff\000-\010\012-\037] *            #  more "normal"
+)*
+<
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+# <
+(?:
+@
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+(?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|
+\[                            # [
+(?: [^\\\x80-\xff\n\015\[\]] |  \\ [^\x80-\xff]  )*     #    stuff
+\]                           #           ]
+)
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+# optional trailing comments
+(?:
+\.
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+(?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|
+\[                            # [
+(?: [^\\\x80-\xff\n\015\[\]] |  \\ [^\x80-\xff]  )*     #    stuff
+\]                           #           ]
+)
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+# optional trailing comments
+)*
+(?: ,
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+@
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+(?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|
+\[                            # [
+(?: [^\\\x80-\xff\n\015\[\]] |  \\ [^\x80-\xff]  )*     #    stuff
+\]                           #           ]
+)
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+# optional trailing comments
+(?:
+\.
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+(?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|
+\[                            # [
+(?: [^\\\x80-\xff\n\015\[\]] |  \\ [^\x80-\xff]  )*     #    stuff
+\]                           #           ]
+)
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+# optional trailing comments
+)*
+)*  # additional domains
+:
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+# optional trailing comments
+)?     #       optional route
+(?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+# Atom
+|                       #  or
+"                                     # "
+[^\\\x80-\xff\n\015"] *                            #   normal
+(?:  \\ [^\x80-\xff]  [^\\\x80-\xff\n\015"] * )*        #   ( special normal* )*
+"                                     #        "
+# Quoted string
+)
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+(?:
+\.
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+(?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+# Atom
+|                       #  or
+"                                     # "
+[^\\\x80-\xff\n\015"] *                            #   normal
+(?:  \\ [^\x80-\xff]  [^\\\x80-\xff\n\015"] * )*        #   ( special normal* )*
+"                                     #        "
+# Quoted string
+)
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+# additional words
+)*
+@
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+(?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|
+\[                            # [
+(?: [^\\\x80-\xff\n\015\[\]] |  \\ [^\x80-\xff]  )*     #    stuff
+\]                           #           ]
+)
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+# optional trailing comments
+(?:
+\.
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+(?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|
+\[                            # [
+(?: [^\\\x80-\xff\n\015\[\]] |  \\ [^\x80-\xff]  )*     #    stuff
+\]                           #           ]
+)
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+# optional trailing comments
+)*
+#       address spec
+>                    #                 >
+# name and address
+)
+/x
+    Alan Other <user\@dom.ain>
+    <user\@dom.ain>
+    user\@dom.ain
+    \"A. Other\" <user.1234\@dom.ain> (a comment)
+    A. Other <user.1234\@dom.ain> (a comment)
+    \"/s=user/ou=host/o=place/prmd=uu.yy/admd= /c=gb/\"\@x400-re.lay
+    A missing angle <user\@some.where
+    *** Failers
+    The quick brown fox
+
+/abc\0def\00pqr\000xyz\0000AB/
+    abc\0def\00pqr\000xyz\0000AB
+    abc456 abc\0def\00pqr\000xyz\0000ABCDE
+
+/abc\x0def\x00pqr\x000xyz\x0000AB/
+    abc\x0def\x00pqr\x000xyz\x0000AB
+    abc456 abc\x0def\x00pqr\x000xyz\x0000ABCDE
+
+/^[\000-\037]/
+    \0A
+    \01B
+    \037C
+
+/\0*/
+    \0\0\0\0
+
+/A\x0{2,3}Z/
+    The A\x0\x0Z
+    An A\0\x0\0Z
+    *** Failers
+    A\0Z
+    A\0\x0\0\x0Z
+
+/^(cow|)\1(bell)/
+    cowcowbell
+    bell
+    *** Failers
+    cowbell
+
+/^\s/
+    \040abc
+    \x0cabc
+    \nabc
+    \rabc
+    \tabc
+    *** Failers
+    abc
+
+/^a	b
+  
    c/x
+    abc
+
+/^(a|)\1*b/
+    ab
+    aaaab
+    b
+    *** Failers
+    acb
+
+/^(a|)\1+b/
+    aab
+    aaaab
+    b
+    *** Failers
+    ab
+
+/^(a|)\1?b/
+    ab
+    aab
+    b
+    *** Failers
+    acb
+
+/^(a|)\1{2}b/
+    aaab
+    b
+    *** Failers
+    ab
+    aab
+    aaaab
+
+/^(a|)\1{2,3}b/
+    aaab
+    aaaab
+    b
+    *** Failers
+    ab
+    aab
+    aaaaab
+
+/ab{1,3}bc/
+    abbbbc
+    abbbc
+    abbc
+    *** Failers
+    abc
+    abbbbbc
+
+/([^.]*)\.([^:]*):[T ]+(.*)/
+    track1.title:TBlah blah blah
+
+/([^.]*)\.([^:]*):[T ]+(.*)/i
+    track1.title:TBlah blah blah
+
+/([^.]*)\.([^:]*):[t ]+(.*)/i
+    track1.title:TBlah blah blah
+
+/^[W-c]+$/
+    WXY_^abc
+    ***Failers
+    wxy
+
+/^[W-c]+$/i
+    WXY_^abc
+    wxy_^ABC
+
+/^[\x3f-\x5F]+$/i
+    WXY_^abc
+    wxy_^ABC
+
+/^abc$/m
+    abc
+    qqq\nabc
+    abc\nzzz
+    qqq\nabc\nzzz
+
+/^abc$/
+    abc
+    *** Failers
+    qqq\nabc
+    abc\nzzz
+    qqq\nabc\nzzz
+
+/\Aabc\Z/m
+    abc
+    *** Failers
+    qqq\nabc
+    abc\nzzz
+    qqq\nabc\nzzz
+
+/\A(.)*\Z/s
+    abc\ndef
+
+/\A(.)*\Z/m
+    *** Failers
+    abc\ndef
+
+/(?:b)|(?::+)/
+    b::c
+    c::b
+
+/[-az]+/
+    az-
+    *** Failers
+    b
+
+/[az-]+/
+    za-
+    *** Failers
+    b
+
+/[a\-z]+/
+    a-z
+    *** Failers
+    b
+
+/[a-z]+/
+    abcdxyz
+
+/[\d-]+/
+    12-34
+    *** Failers
+    aaa
+
+/[\d-z]+/
+    12-34z
+    *** Failers
+    aaa
+
+/\x5c/
+    \\
+
+/\x20Z/
+    the Zoo
+    *** Failers
+    Zulu
+
+/(abc)\1/i
+    abcabc
+    ABCabc
+    abcABC
+
+/(main(OPT)?)+/
+    mainmain
+    mainOPTmain
+
+/ab{3cd/
+    ab{3cd
+
+/ab{3,cd/
+    ab{3,cd
+
+/ab{3,4a}cd/
+    ab{3,4a}cd
+
+/{4,5a}bc/
+    {4,5a}bc
+
+/^a.b/
+    a\rb
+    *** Failers
+    a\nb
+
+/abc$/
+    abc
+    abc\n
+    *** Failers
+    abc\ndef
+
+/(abc)\123/
+    abc\x53
+
+/(abc)\223/
+    abc\x93
+
+/(abc)\323/
+    abc\xd3
+
+/(abc)\500/
+    abc\x40
+    abc\100
+
+/(abc)\5000/
+    abc\x400
+    abc\x40\x30
+    abc\1000
+    abc\100\x30
+    abc\100\060
+    abc\100\60
+
+/abc\81/
+   abc\081
+   abc\0\x38\x31
+
+/abc\91/
+   abc\091
+   abc\0\x39\x31
+
+/(a)(b)(c)(d)(e)(f)(g)(h)(i)(j)(k)(l)\12\123/
+    abcdefghijkllS
+
+/(a)(b)(c)(d)(e)(f)(g)(h)(i)(j)(k)\12\123/
+    abcdefghijk\12S
+
+/ab\gdef/
+    abgdef
+
+/a{0}bc/
+    bc
+
+/(a|(bc)){0,0}?xyz/
+    xyz
+
+/abc[\10]de/
+    abc\010de
+
+/abc[\1]de/
+    abc\1de
+
+/(abc)[\1]de/
+    abc\1de
+
+/a.b(?s)/
+    a\nb
+
+/^([^a])([^\b])([^c]*)([^d]{3,4})/
+    baNOTccccd
+    baNOTcccd
+    baNOTccd
+    bacccd
+    *** Failers
+    anything
+    b\bc   
+    baccd
+
+/[^a]/
+  Abc
+  
+/[^a]/i
+  Abc 
+
+/[^a]+/
+  AAAaAbc
+  
+/[^a]+/i
+  AAAaAbc 
+
+/[^a]+/
+   bbb\nccc
+
+/ End of test input /
diff --git a/testinput2 b/testinput2
new file mode 100644
index 0000000..6a164d6
--- /dev/null
+++ b/testinput2
@@ -0,0 +1,244 @@
+/(a)b|/
+
+/(a*)*/
+
+/(abc|)+/
+
+/abc/
+    abc
+    defabc
+    \Aabc
+    \IABC
+    *** Failers
+    \Adefabc
+    ABC
+
+/^abc/
+    abc
+    \Aabc
+    *** Failers
+    defabc
+    \Adefabc
+
+/a+bc/
+
+/a*bc/
+
+/a{3}bc/
+
+/(abc|a+z)/
+
+/^abc$/
+    abc
+    \Mdef\nabc
+    *** Failers
+    def\nabc
+
+/abc\/
+
+/ab\gdef/X
+
+/x{5,4}/
+
+/z{65536}/
+
+/[abcd/
+
+/[\B]/
+
+/[a-\w]/
+
+/[z-a]/
+
+/^*/
+
+/(abc/
+
+/(?# abc/
+
+/(?z)abc/
+
+/.*b/
+
+/.*?b/
+
+/cat|dog|elephant/
+    this sentence eventually mentions a cat
+    this sentences rambles on and on for a while and then reaches elephant
+
+/cat|dog|elephant/S
+    this sentence eventually mentions a cat
+    this sentences rambles on and on for a while and then reaches elephant
+
+/cat|dog|elephant/iS
+    this sentence eventually mentions a CAT cat
+    this sentences rambles on and on for a while to elephant ElePhant
+
+/cat|dog|elephant/IS
+    this sentence eventually mentions a CAT cat
+    this sentences rambles on and on for a while to elephant ElePhant
+
+/cat|dog|elephant/IS
+    \Ithis sentence eventually mentions a CAT cat
+    \Ithis sentences rambles on and on for a while to elephant ElePhant
+
+/a|[bcd]/S
+
+/(a|[^\dZ])/S
+
+/(a|b)*[\s]/S
+
+/(ab\2)/
+
+/{4,5}abc/
+
+/(a)(b)(c)\2/
+    abcb
+    \O0abcb
+    \O2abcb
+    \O4abcb
+    \O6abcb
+    \O8abcb
+
+/(a)bc|(a)(b)\2/
+    abc
+    \O0abc
+    \O2abc
+    \O4abc
+    aba
+    \O0aba
+    \O2aba
+    \O4aba
+    \O6aba
+    \O8aba
+
+/^a.b/
+    \Sa\nb
+
+/abc$/E
+    abc
+    *** Failers
+    abc\n
+    abc\ndef
+
+/abc$/
+    *** Failers
+    \Eabc\n
+    \Eabc\ndef
+
+/abc$/m
+    \Eabc\n
+    \Eabc\ndef
+
+/(a)(b)(c)(d)(e)\6/
+
+/the quick brown fox/
+    the quick brown fox
+    this is a line with the quick brown fox
+
+/the quick brown fox/A
+    the quick brown fox
+    *** Failers
+    this is a line with the quick brown fox
+
+/ab(?z)cd/
+
+".*/\Xfoo"X
+    /this/is/a/very/long/line/in/deed/with/very/many/slashes/in/it/you/see/
+
+".*/\Xfoo"X
+    /this/is/a/very/long/line/in/deed/with/very/many/slashes/in/and/foo
+
+/(\.\d\d[1-9]?)\d+/
+    1.230003938
+    1.875000282
+    1.235 
+
+/(\.\d\d[1-9]?)\X\d+/X
+    1.230003938
+    1.875000282
+    *** Failers 
+    1.235 
+
+/(\.\d\d((?=0)|\d(?=\d)))/
+    1.230003938
+    1.875000282
+    *** Failers 
+    1.235 
+
+/^(\w+\X|\s+\X)*$/X
+    now is the time for all good men to come to the aid of the party
+    *** Failers
+    this is not a line with only words and spaces!
+    
+/^abc|def/
+    abcdef
+    abcdef\B
+
+/.*((abc)$|(def))/
+    defabc
+    \Zdefabc
+
+/abc/P
+    abc
+    *** Failers
+    
+/^abc|def/P
+    abcdef
+    abcdef\B
+
+/.*((abc)$|(def))/P
+    defabc
+    \Zdefabc
+  
+/the quick brown fox/P
+    the quick brown fox
+    *** Failers 
+    The Quick Brown Fox 
+
+/the quick brown fox/Pi
+    the quick brown fox
+    The Quick Brown Fox 
+
+/abc.def/P
+    *** Failers
+    abc\ndef
+    
+/abc$/P
+    abc
+    abc\n 
+
+/abc\/P
+
+/(abc)\2/P
+
+/(abc\1)/P
+    abc
+
+"(?>.*/)foo"X
+    /this/is/a/very/long/line/in/deed/with/very/many/slashes/in/it/you/see/
+
+"(?>.*/)foo"X
+    /this/is/a/very/long/line/in/deed/with/very/many/slashes/in/and/foo
+
+/(?>(\.\d\d[1-9]?))\d+/X
+    1.230003938
+    1.875000282
+    *** Failers 
+    1.235 
+
+/^((?>\w+)|(?>\s+))*$/X
+    now is the time for all good men to come to the aid of the party
+    *** Failers
+    this is not a line with only words and spaces!
+    
+/(\d+)(\w)/X
+    12345a
+    12345+ 
+
+/((?>\d+))(\w)/X
+    12345a
+    *** Failers
+    12345+ 
+
+/ End of test input /
diff --git a/testoutput b/testoutput
new file mode 100644
index 0000000..0c924d7
--- /dev/null
+++ b/testoutput
@@ -0,0 +1,2298 @@
+Testing Perl-Compatible Regular Expressions
+PCRE version 1.00 18-Nov-1997
+
+/the quick brown fox/
+    the quick brown fox
+ 0: the quick brown fox
+    The quick brown FOX
+No match
+    What do you know about the quick brown fox?
+ 0: the quick brown fox
+    What do you know about THE QUICK BROWN FOX?
+No match
+
+/The quick brown fox/i
+    the quick brown fox
+ 0: the quick brown fox
+    The quick brown FOX
+ 0: The quick brown FOX
+    What do you know about the quick brown fox?
+ 0: the quick brown fox
+    What do you know about THE QUICK BROWN FOX?
+ 0: THE QUICK BROWN FOX
+
+/abcd\t\n\r\f\a\e\071\x3b\$\\\?caxyz/
+    abcd\t\n\r\f\a\e9;\$\\?caxyz
+ 0: abcd\x09\x0a\x0d\x0c\x07\x1b9;$\?caxyz
+
+/a*abc?xyz+pqr{3}ab{2,}xy{4,5}pq{0,6}AB{0,}zz/
+    abxyzpqrrrabbxyyyypqAzz
+ 0: abxyzpqrrrabbxyyyypqAzz
+    abxyzpqrrrabbxyyyypqAzz
+ 0: abxyzpqrrrabbxyyyypqAzz
+    aabxyzpqrrrabbxyyyypqAzz
+ 0: aabxyzpqrrrabbxyyyypqAzz
+    aaabxyzpqrrrabbxyyyypqAzz
+ 0: aaabxyzpqrrrabbxyyyypqAzz
+    aaaabxyzpqrrrabbxyyyypqAzz
+ 0: aaaabxyzpqrrrabbxyyyypqAzz
+    abcxyzpqrrrabbxyyyypqAzz
+ 0: abcxyzpqrrrabbxyyyypqAzz
+    aabcxyzpqrrrabbxyyyypqAzz
+ 0: aabcxyzpqrrrabbxyyyypqAzz
+    aaabcxyzpqrrrabbxyyyypAzz
+ 0: aaabcxyzpqrrrabbxyyyypAzz
+    aaabcxyzpqrrrabbxyyyypqAzz
+ 0: aaabcxyzpqrrrabbxyyyypqAzz
+    aaabcxyzpqrrrabbxyyyypqqAzz
+ 0: aaabcxyzpqrrrabbxyyyypqqAzz
+    aaabcxyzpqrrrabbxyyyypqqqAzz
+ 0: aaabcxyzpqrrrabbxyyyypqqqAzz
+    aaabcxyzpqrrrabbxyyyypqqqqAzz
+ 0: aaabcxyzpqrrrabbxyyyypqqqqAzz
+    aaabcxyzpqrrrabbxyyyypqqqqqAzz
+ 0: aaabcxyzpqrrrabbxyyyypqqqqqAzz
+    aaabcxyzpqrrrabbxyyyypqqqqqqAzz
+ 0: aaabcxyzpqrrrabbxyyyypqqqqqqAzz
+    aaaabcxyzpqrrrabbxyyyypqAzz
+ 0: aaaabcxyzpqrrrabbxyyyypqAzz
+    abxyzzpqrrrabbxyyyypqAzz
+ 0: abxyzzpqrrrabbxyyyypqAzz
+    aabxyzzzpqrrrabbxyyyypqAzz
+ 0: aabxyzzzpqrrrabbxyyyypqAzz
+    aaabxyzzzzpqrrrabbxyyyypqAzz
+ 0: aaabxyzzzzpqrrrabbxyyyypqAzz
+    aaaabxyzzzzpqrrrabbxyyyypqAzz
+ 0: aaaabxyzzzzpqrrrabbxyyyypqAzz
+    abcxyzzpqrrrabbxyyyypqAzz
+ 0: abcxyzzpqrrrabbxyyyypqAzz
+    aabcxyzzzpqrrrabbxyyyypqAzz
+ 0: aabcxyzzzpqrrrabbxyyyypqAzz
+    aaabcxyzzzzpqrrrabbxyyyypqAzz
+ 0: aaabcxyzzzzpqrrrabbxyyyypqAzz
+    aaaabcxyzzzzpqrrrabbxyyyypqAzz
+ 0: aaaabcxyzzzzpqrrrabbxyyyypqAzz
+    aaaabcxyzzzzpqrrrabbbxyyyypqAzz
+ 0: aaaabcxyzzzzpqrrrabbbxyyyypqAzz
+    aaaabcxyzzzzpqrrrabbbxyyyyypqAzz
+ 0: aaaabcxyzzzzpqrrrabbbxyyyyypqAzz
+    aaabcxyzpqrrrabbxyyyypABzz
+ 0: aaabcxyzpqrrrabbxyyyypABzz
+    aaabcxyzpqrrrabbxyyyypABBzz
+ 0: aaabcxyzpqrrrabbxyyyypABBzz
+    >>>aaabxyzpqrrrabbxyyyypqAzz
+ 0: aaabxyzpqrrrabbxyyyypqAzz
+    >aaaabxyzpqrrrabbxyyyypqAzz
+ 0: aaaabxyzpqrrrabbxyyyypqAzz
+    >>>>abcxyzpqrrrabbxyyyypqAzz
+ 0: abcxyzpqrrrabbxyyyypqAzz
+    *** Failers
+No match
+    abxyzpqrrabbxyyyypqAzz
+No match
+    abxyzpqrrrrabbxyyyypqAzz
+No match
+    abxyzpqrrrabxyyyypqAzz
+No match
+    aaaabcxyzzzzpqrrrabbbxyyyyyypqAzz
+No match
+    aaaabcxyzzzzpqrrrabbbxyyypqAzz
+No match
+    aaabcxyzpqrrrabbxyyyypqqqqqqqAzz
+No match
+
+/^(abc){1,2}zz/
+    abczz
+ 0: abczz
+ 1: abc
+    abcabczz
+ 0: abcabczz
+ 1: abc
+    *** Failers
+No match
+    zz
+No match
+    abcabcabczz
+No match
+    >>abczz
+No match
+
+/^(b+?|a){1,2}?c/
+    bc
+ 0: bc
+ 1: b
+    bbc
+ 0: bbc
+ 1: b
+    bbbc
+ 0: bbbc
+ 1: bb
+    bac
+ 0: bac
+ 1: a
+    bbac
+ 0: bbac
+ 1: a
+    aac
+ 0: aac
+ 1: a
+    abbbbbbbbbbbc
+ 0: abbbbbbbbbbbc
+ 1: bbbbbbbbbbb
+    bbbbbbbbbbbac
+ 0: bbbbbbbbbbbac
+ 1: a
+    *** Failers
+No match
+    aaac
+No match
+    abbbbbbbbbbbac
+No match
+
+/^(b+|a){1,2}c/
+    bc
+ 0: bc
+ 1: b
+    bbc
+ 0: bbc
+ 1: bb
+    bbbc
+ 0: bbbc
+ 1: bbb
+    bac
+ 0: bac
+ 1: a
+    bbac
+ 0: bbac
+ 1: a
+    aac
+ 0: aac
+ 1: a
+    abbbbbbbbbbbc
+ 0: abbbbbbbbbbbc
+ 1: bbbbbbbbbbb
+    bbbbbbbbbbbac
+ 0: bbbbbbbbbbbac
+ 1: a
+    *** Failers
+No match
+    aaac
+No match
+    abbbbbbbbbbbac
+No match
+
+/^(b+|a){1,2}?bc/
+    bbc
+ 0: bbc
+ 1: b
+
+/^(b*|ba){1,2}?bc/
+    babc
+ 0: babc
+ 1: ba
+    bbabc
+ 0: bbabc
+ 1: ba
+    bababc
+ 0: bababc
+ 1: ba
+    *** Failers
+No match
+    bababbc
+No match
+    babababc
+No match
+
+/^(ba|b*){1,2}?bc/
+    babc
+ 0: babc
+ 1: ba
+    bbabc
+ 0: bbabc
+ 1: ba
+    bababc
+ 0: bababc
+ 1: ba
+    *** Failers
+No match
+    bababbc
+No match
+    babababc
+No match
+
+/^\ca\cA\c[\c{\c:/
+    \x01\x01\e;z
+ 0: \x01\x01\x1b;z
+
+/^[ab\]cde]/
+    athing
+ 0: a
+    bthing
+ 0: b
+    ]thing
+ 0: ]
+    cthing
+ 0: c
+    dthing
+ 0: d
+    ething
+ 0: e
+    *** Failers
+No match
+    fthing
+No match
+    [thing
+No match
+    \\thing
+No match
+
+/^[]cde]/
+    ]thing
+ 0: ]
+    cthing
+ 0: c
+    dthing
+ 0: d
+    ething
+ 0: e
+    *** Failers
+No match
+    athing
+No match
+    fthing
+No match
+
+/^[^ab\]cde]/
+    fthing
+ 0: f
+    [thing
+ 0: [
+    \\thing
+ 0: \
+    *** Failers
+ 0: *
+    athing
+No match
+    bthing
+No match
+    ]thing
+No match
+    cthing
+No match
+    dthing
+No match
+    ething
+No match
+
+/^[^]cde]/
+    athing
+ 0: a
+    fthing
+ 0: f
+    *** Failers
+ 0: *
+    ]thing
+No match
+    cthing
+No match
+    dthing
+No match
+    ething
+No match
+
+/^\�/
+    �
+ 0: \x81
+
+/^ÿ/
+    ÿ
+ 0: \xff
+
+/^[0-9]+$/
+    0
+ 0: 0
+    1
+ 0: 1
+    2
+ 0: 2
+    3
+ 0: 3
+    4
+ 0: 4
+    5
+ 0: 5
+    6
+ 0: 6
+    7
+ 0: 7
+    8
+ 0: 8
+    9
+ 0: 9
+    10
+ 0: 10
+    100
+ 0: 100
+    *** Failers
+No match
+    abc
+No match
+
+/^.*nter/
+    enter
+ 0: enter
+    inter
+ 0: inter
+    uponter
+ 0: uponter
+
+/^xxx[0-9]+$/
+    xxx0
+ 0: xxx0
+    xxx1234
+ 0: xxx1234
+    *** Failers
+No match
+    xxx
+No match
+
+/^.+[0-9][0-9][0-9]$/
+    x123
+ 0: x123
+    xx123
+ 0: xx123
+    123456
+ 0: 123456
+    *** Failers
+No match
+    123
+No match
+    x1234
+ 0: x1234
+
+/^.+?[0-9][0-9][0-9]$/
+    x123
+ 0: x123
+    xx123
+ 0: xx123
+    123456
+ 0: 123456
+    *** Failers
+No match
+    123
+No match
+    x1234
+ 0: x1234
+
+/^([^!]+)!(.+)=apquxz\.ixr\.zzz\.ac\.uk$/
+    abc!pqr=apquxz.ixr.zzz.ac.uk
+ 0: abc!pqr=apquxz.ixr.zzz.ac.uk
+ 1: abc
+ 2: pqr
+    *** Failers
+No match
+    !pqr=apquxz.ixr.zzz.ac.uk
+No match
+    abc!=apquxz.ixr.zzz.ac.uk
+No match
+    abc!pqr=apquxz:ixr.zzz.ac.uk
+No match
+    abc!pqr=apquxz.ixr.zzz.ac.ukk
+No match
+
+/:/
+    Well, we need a colon: somewhere
+ 0: :
+    *** Fail if we don't
+No match
+
+/([\da-f:]+)$/i
+    0abc
+ 0: 0abc
+ 1: 0abc
+    abc
+ 0: abc
+ 1: abc
+    fed
+ 0: fed
+ 1: fed
+    E
+ 0: E
+ 1: E
+    ::
+ 0: ::
+ 1: ::
+    5f03:12C0::932e
+ 0: 5f03:12C0::932e
+ 1: 5f03:12C0::932e
+    fed def
+ 0: def
+ 1: def
+    Any old stuff
+ 0: ff
+ 1: ff
+    *** Failers
+No match
+    0zzz
+No match
+    gzzz
+No match
+    fed\x20
+No match
+    Any old rubbish
+No match
+
+/^.*\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})$/
+    .1.2.3
+ 0: .1.2.3
+ 1: 1
+ 2: 2
+ 3: 3
+    A.12.123.0
+ 0: A.12.123.0
+ 1: 12
+ 2: 123
+ 3: 0
+    *** Failers
+No match
+    .1.2.3333
+No match
+    1.2.3
+No match
+    1234.2.3
+No match
+
+/^(\d+)\s+IN\s+SOA\s+(\S+)\s+(\S+)\s*\(\s*$/
+    1 IN SOA non-sp1 non-sp2(
+ 0: 1 IN SOA non-sp1 non-sp2(
+ 1: 1
+ 2: non-sp1
+ 3: non-sp2
+    1    IN    SOA    non-sp1    non-sp2   (
+ 0: 1    IN    SOA    non-sp1    non-sp2   (
+ 1: 1
+ 2: non-sp1
+ 3: non-sp2
+    *** Failers
+No match
+    1IN SOA non-sp1 non-sp2(
+No match
+
+/^[a-zA-Z\d][a-zA-Z\d\-]*(\.[a-zA-Z\d][a-zA-z\d\-]*)*\.$/
+    a.
+ 0: a.
+    Z.
+ 0: Z.
+    2.
+ 0: 2.
+    ab-c.pq-r.
+ 0: ab-c.pq-r.
+ 1: .pq-r
+    sxk.zzz.ac.uk.
+ 0: sxk.zzz.ac.uk.
+ 1: .uk
+    x-.y-.
+ 0: x-.y-.
+ 1: .y-
+    *** Failers
+No match
+    -abc.peq.
+No match
+
+/^\*\.[a-z]([a-z\-\d]*[a-z\d]+)?(\.[a-z]([a-z\-\d]*[a-z\d]+)?)*$/
+    *.a
+ 0: *.a
+    *.b0-a
+ 0: *.b0-a
+ 1: 0-a
+    *.c3-b.c
+ 0: *.c3-b.c
+ 1: 3-b
+ 2: .c
+    *.c-a.b-c
+ 0: *.c-a.b-c
+ 1: -a
+ 2: .b-c
+ 3: -c
+    *** Failers
+No match
+    *.0
+No match
+    *.a-
+No match
+    *.a-b.c-
+No match
+    *.c-a.0-c
+No match
+
+/^(?=ab(de))(abd)(e)/
+    abde
+ 0: abde
+ 1: de
+ 2: abd
+ 3: e
+
+/^(?!(ab)de|x)(abd)(f)/
+    abdf
+ 0: abdf
+ 1: <unset>
+ 2: abd
+ 3: f
+
+/^(?=(ab(cd)))(ab)/
+    abcd
+ 0: ab
+ 1: abcd
+ 2: cd
+ 3: ab
+
+/^[\da-f](\.[\da-f])*$/i
+    a.b.c.d
+ 0: a.b.c.d
+ 1: .d
+    A.B.C.D
+ 0: A.B.C.D
+ 1: .D
+    a.b.c.1.2.3.C
+ 0: a.b.c.1.2.3.C
+ 1: .C
+
+/^\".*\"\s*(;.*)?$/
+    \"1234\"
+ 0: "1234"
+    \"abcd\" ;
+ 0: "abcd" ;
+ 1: ;
+    \"\" ; rhubarb
+ 0: "" ; rhubarb
+ 1: ; rhubarb
+    *** Failers
+No match
+    \"1234\" : things
+No match
+
+/^$/
+    \
+ 0: 
+    *** Failers
+No match
+
+/   ^    a   (?# begins with a)  b\sc (?# then b c) $ (?# then end)/x
+    ab c
+ 0: ab c
+    *** Failers
+No match
+    abc
+No match
+    ab cde
+No match
+
+/(?x)   ^    a   (?# begins with a)  b\sc (?# then b c) $ (?# then end)/
+    ab c
+ 0: ab c
+    *** Failers
+No match
+    abc
+No match
+    ab cde
+No match
+
+/^   a\ b[c ]d       $/x
+    a bcd
+ 0: a bcd
+    a b d
+ 0: a b d
+    *** Failers
+No match
+    abcd
+No match
+    ab d
+No match
+
+/^(a(b(c)))(d(e(f)))(h(i(j)))(k(l(m)))$/
+    abcdefhijklm
+ 0: abcdefhijklm
+ 1: abc
+ 2: bc
+ 3: c
+ 4: def
+ 5: ef
+ 6: f
+ 7: hij
+ 8: ij
+ 9: j
+10: klm
+11: lm
+12: m
+
+/^(?:a(b(c)))(?:d(e(f)))(?:h(i(j)))(?:k(l(m)))$/
+    abcdefhijklm
+ 0: abcdefhijklm
+ 1: bc
+ 2: c
+ 3: ef
+ 4: f
+ 5: ij
+ 6: j
+ 7: lm
+ 8: m
+
+/^[\w][\W][\s][\S][\d][\D][\b][\n][\c]][\022]/
+    a+ Z0+\x08\n\x1d\x12
+ 0: a+ Z0+\x08\x0a\x1d\x12
+
+/^[.^$|()*+?{,}]+/
+    .^\$(*+)|{?,?}
+ 0: .^$(*+)|{?,?}
+
+/^a*\w/
+    z
+ 0: z
+    az
+ 0: az
+    aaaz
+ 0: aaaz
+    a
+ 0: a
+    aa
+ 0: aa
+    aaaa
+ 0: aaaa
+    a+
+ 0: a
+    aa+
+ 0: aa
+
+/^a*?\w/
+    z
+ 0: z
+    az
+ 0: a
+    aaaz
+ 0: a
+    a
+ 0: a
+    aa
+ 0: a
+    aaaa
+ 0: a
+    a+
+ 0: a
+    aa+
+ 0: a
+
+/^a+\w/
+    az
+ 0: az
+    aaaz
+ 0: aaaz
+    aa
+ 0: aa
+    aaaa
+ 0: aaaa
+    aa+
+ 0: aa
+
+/^a+?\w/
+    az
+ 0: az
+    aaaz
+ 0: aa
+    aa
+ 0: aa
+    aaaa
+ 0: aa
+    aa+
+ 0: aa
+
+/^\d{8}\w{2,}/
+    1234567890
+ 0: 1234567890
+    12345678ab
+ 0: 12345678ab
+    12345678__
+ 0: 12345678__
+    *** Failers
+No match
+    1234567
+No match
+
+/^[aeiou\d]{4,5}$/
+    uoie
+ 0: uoie
+    1234
+ 0: 1234
+    12345
+ 0: 12345
+    aaaaa
+ 0: aaaaa
+    *** Failers
+No match
+    123456
+No match
+
+/^[aeiou\d]{4,5}?/
+    uoie
+ 0: uoie
+    1234
+ 0: 1234
+    12345
+ 0: 1234
+    aaaaa
+ 0: aaaa
+    123456
+ 0: 1234
+
+/\A(abc|def)=(\1){2,3}\Z/
+    abc=abcabc
+ 0: abc=abcabc
+ 1: abc
+ 2: abc
+    def=defdefdef
+ 0: def=defdefdef
+ 1: def
+ 2: def
+    *** Failers
+No match
+    abc=defdef
+No match
+
+/^(a)(b)(c)(d)(e)(f)(g)(h)(i)(j)(k)\11*(\3\4)\1(?#)2$/
+    abcdefghijkcda2
+ 0: abcdefghijkcda2
+ 1: a
+ 2: b
+ 3: c
+ 4: d
+ 5: e
+ 6: f
+ 7: g
+ 8: h
+ 9: i
+10: j
+11: k
+12: cd
+    abcdefghijkkkkcda2
+ 0: abcdefghijkkkkcda2
+ 1: a
+ 2: b
+ 3: c
+ 4: d
+ 5: e
+ 6: f
+ 7: g
+ 8: h
+ 9: i
+10: j
+11: k
+12: cd
+
+/(cat(a(ract|tonic)|erpillar)) \1()2(3)/
+    cataract cataract23
+ 0: cataract cataract23
+ 1: cataract
+ 2: aract
+ 3: ract
+ 4: 
+ 5: 3
+    catatonic catatonic23
+ 0: catatonic catatonic23
+ 1: catatonic
+ 2: atonic
+ 3: tonic
+ 4: 
+ 5: 3
+    caterpillar caterpillar23
+ 0: caterpillar caterpillar23
+ 1: caterpillar
+ 2: erpillar
+ 3: <unset>
+ 4: 
+ 5: 3
+
+
+/^From +([^ ]+) +[a-zA-Z][a-zA-Z][a-zA-Z] +[a-zA-Z][a-zA-Z][a-zA-Z] +[0-9]?[0-9] +[0-9][0-9]:[0-9][0-9]/
+    From abcd  Mon Sep 01 12:33:02 1997
+ 0: From abcd  Mon Sep 01 12:33
+ 1: abcd
+
+/^From\s+\S+\s+([a-zA-Z]{3}\s+){2}\d{1,2}\s+\d\d:\d\d/
+    From abcd  Mon Sep 01 12:33:02 1997
+ 0: From abcd  Mon Sep 01 12:33
+ 1: Sep 
+    From abcd  Mon Sep  1 12:33:02 1997
+ 0: From abcd  Mon Sep  1 12:33
+ 1: Sep  
+    *** Failers
+No match
+    From abcd  Sep 01 12:33:02 1997
+No match
+
+/^12.34/s
+    12\n34
+ 0: 12\x0a34
+    12\r34
+ 0: 12\x0d34
+
+/\w+(?=\t)/
+    the quick brown\t fox
+ 0: brown
+
+/foo(?!bar)(.*)/
+    foobar is foolish see?
+ 0: foolish see?
+ 1: lish see?
+
+/(?:(?!foo)...|^.{0,2})bar(.*)/
+    foobar crowbar etc
+ 0: rowbar etc
+ 1:  etc
+    barrel
+ 0: barrel
+ 1: rel
+    2barrel
+ 0: 2barrel
+ 1: rel
+    A barrel
+ 0: A barrel
+ 1: rel
+
+/^(\D*)(?=\d)(?!123)/
+    abc456
+ 0: abc
+ 1: abc
+    *** Failers
+No match
+    abc123
+No match
+
+/^1234(?# test newlines
+  inside)/
+    1234
+ 0: 1234
+
+/^1234 #comment in extended re
+  /x
+    1234
+ 0: 1234
+
+/#rhubarb
+  abcd/x
+    abcd
+ 0: abcd
+
+/^abcd#rhubarb/x
+    abcd
+ 0: abcd
+
+/^(a)\1{2,3}(.)/
+    aaab
+ 0: aaab
+ 1: a
+ 2: b
+    aaaab
+ 0: aaaab
+ 1: a
+ 2: b
+    aaaaab
+ 0: aaaaa
+ 1: a
+ 2: a
+    aaaaaab
+ 0: aaaaa
+ 1: a
+ 2: a
+
+/(?!^)abc/
+    the abc
+ 0: abc
+    *** Failers
+No match
+    abc
+No match
+
+/(?=^)abc/
+    abc
+ 0: abc
+    *** Failers
+No match
+    the abc
+No match
+
+/^[ab]{1,3}(ab*|b)/
+    aabbbbb
+ 0: aabb
+ 1: b
+
+/^[ab]{1,3}?(ab*|b)/
+    aabbbbb
+ 0: aabbbbb
+ 1: abbbbb
+
+/^[ab]{1,3}?(ab*?|b)/
+    aabbbbb
+ 0: aa
+ 1: a
+
+/^[ab]{1,3}(ab*?|b)/
+    aabbbbb
+ 0: aabb
+ 1: b
+
+/  (?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*                          # optional leading comment
+(?:    (?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|
+" (?:                      # opening quote...
+[^\\\x80-\xff\n\015"]                #   Anything except backslash and quote
+|                     #    or
+\\ [^\x80-\xff]           #   Escaped something (something != CR)
+)* "  # closing quote
+)                    # initial word
+(?:  (?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*  \.  (?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*   (?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|
+" (?:                      # opening quote...
+[^\\\x80-\xff\n\015"]                #   Anything except backslash and quote
+|                     #    or
+\\ [^\x80-\xff]           #   Escaped something (something != CR)
+)* "  # closing quote
+)  )* # further okay, if led by a period
+(?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*  @  (?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*    (?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|   \[                         # [
+(?: [^\\\x80-\xff\n\015\[\]] |  \\ [^\x80-\xff]  )*    #    stuff
+\]                        #           ]
+)                           # initial subdomain
+(?:                                  #
+(?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*  \.                        # if led by a period...
+(?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*   (?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|   \[                         # [
+(?: [^\\\x80-\xff\n\015\[\]] |  \\ [^\x80-\xff]  )*    #    stuff
+\]                        #           ]
+)                     #   ...further okay
+)*
+# address
+|                     #  or
+(?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|
+" (?:                      # opening quote...
+[^\\\x80-\xff\n\015"]                #   Anything except backslash and quote
+|                     #    or
+\\ [^\x80-\xff]           #   Escaped something (something != CR)
+)* "  # closing quote
+)             # one word, optionally followed by....
+(?:
+[^()<>@,;:".\\\[\]\x80-\xff\000-\010\012-\037]  |  # atom and space parts, or...
+\(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)       |  # comments, or...
+
+" (?:                      # opening quote...
+[^\\\x80-\xff\n\015"]                #   Anything except backslash and quote
+|                     #    or
+\\ [^\x80-\xff]           #   Escaped something (something != CR)
+)* "  # closing quote
+# quoted strings
+)*
+<  (?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*                     # leading <
+(?:  @  (?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*    (?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|   \[                         # [
+(?: [^\\\x80-\xff\n\015\[\]] |  \\ [^\x80-\xff]  )*    #    stuff
+\]                        #           ]
+)                           # initial subdomain
+(?:                                  #
+(?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*  \.                        # if led by a period...
+(?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*   (?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|   \[                         # [
+(?: [^\\\x80-\xff\n\015\[\]] |  \\ [^\x80-\xff]  )*    #    stuff
+\]                        #           ]
+)                     #   ...further okay
+)*
+
+(?:  (?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*  ,  (?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*  @  (?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*    (?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|   \[                         # [
+(?: [^\\\x80-\xff\n\015\[\]] |  \\ [^\x80-\xff]  )*    #    stuff
+\]                        #           ]
+)                           # initial subdomain
+(?:                                  #
+(?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*  \.                        # if led by a period...
+(?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*   (?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|   \[                         # [
+(?: [^\\\x80-\xff\n\015\[\]] |  \\ [^\x80-\xff]  )*    #    stuff
+\]                        #           ]
+)                     #   ...further okay
+)*
+)* # further okay, if led by comma
+:                                # closing colon
+(?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*  )? #       optional route
+(?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|
+" (?:                      # opening quote...
+[^\\\x80-\xff\n\015"]                #   Anything except backslash and quote
+|                     #    or
+\\ [^\x80-\xff]           #   Escaped something (something != CR)
+)* "  # closing quote
+)                    # initial word
+(?:  (?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*  \.  (?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*   (?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|
+" (?:                      # opening quote...
+[^\\\x80-\xff\n\015"]                #   Anything except backslash and quote
+|                     #    or
+\\ [^\x80-\xff]           #   Escaped something (something != CR)
+)* "  # closing quote
+)  )* # further okay, if led by a period
+(?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*  @  (?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*    (?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|   \[                         # [
+(?: [^\\\x80-\xff\n\015\[\]] |  \\ [^\x80-\xff]  )*    #    stuff
+\]                        #           ]
+)                           # initial subdomain
+(?:                                  #
+(?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*  \.                        # if led by a period...
+(?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*   (?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|   \[                         # [
+(?: [^\\\x80-\xff\n\015\[\]] |  \\ [^\x80-\xff]  )*    #    stuff
+\]                        #           ]
+)                     #   ...further okay
+)*
+#       address spec
+(?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*  > #                  trailing >
+# name and address
+)  (?: [\040\t] |  \(
+(?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  |  \( (?:  [^\\\x80-\xff\n\015()]  |  \\ [^\x80-\xff]  )* \)  )*
+\)  )*                       # optional trailing comment
+/x
+    Alan Other <user\@dom.ain>
+ 0: Alan Other <user@dom.ain>
+    <user\@dom.ain>
+ 0: user@dom.ain
+    user\@dom.ain
+ 0: user@dom.ain
+    \"A. Other\" <user.1234\@dom.ain> (a comment)
+ 0: "A. Other" <user.1234@dom.ain> (a comment)
+    A. Other <user.1234\@dom.ain> (a comment)
+ 0:  Other <user.1234@dom.ain> (a comment)
+    \"/s=user/ou=host/o=place/prmd=uu.yy/admd= /c=gb/\"\@x400-re.lay
+ 0: "/s=user/ou=host/o=place/prmd=uu.yy/admd= /c=gb/"@x400-re.lay
+    A missing angle <user\@some.where
+ 0: user@some.where
+    *** Failers
+No match
+    The quick brown fox
+No match
+
+/[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+# optional leading comment
+(?:
+(?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+# Atom
+|                       #  or
+"                                     # "
+[^\\\x80-\xff\n\015"] *                            #   normal
+(?:  \\ [^\x80-\xff]  [^\\\x80-\xff\n\015"] * )*        #   ( special normal* )*
+"                                     #        "
+# Quoted string
+)
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+(?:
+\.
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+(?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+# Atom
+|                       #  or
+"                                     # "
+[^\\\x80-\xff\n\015"] *                            #   normal
+(?:  \\ [^\x80-\xff]  [^\\\x80-\xff\n\015"] * )*        #   ( special normal* )*
+"                                     #        "
+# Quoted string
+)
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+# additional words
+)*
+@
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+(?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|
+\[                            # [
+(?: [^\\\x80-\xff\n\015\[\]] |  \\ [^\x80-\xff]  )*     #    stuff
+\]                           #           ]
+)
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+# optional trailing comments
+(?:
+\.
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+(?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|
+\[                            # [
+(?: [^\\\x80-\xff\n\015\[\]] |  \\ [^\x80-\xff]  )*     #    stuff
+\]                           #           ]
+)
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+# optional trailing comments
+)*
+# address
+|                             #  or
+(?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+# Atom
+|                       #  or
+"                                     # "
+[^\\\x80-\xff\n\015"] *                            #   normal
+(?:  \\ [^\x80-\xff]  [^\\\x80-\xff\n\015"] * )*        #   ( special normal* )*
+"                                     #        "
+# Quoted string
+)
+# leading word
+[^()<>@,;:".\\\[\]\x80-\xff\000-\010\012-\037] *               # "normal" atoms and or spaces
+(?:
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+|
+"                                     # "
+[^\\\x80-\xff\n\015"] *                            #   normal
+(?:  \\ [^\x80-\xff]  [^\\\x80-\xff\n\015"] * )*        #   ( special normal* )*
+"                                     #        "
+) # "special" comment or quoted string
+[^()<>@,;:".\\\[\]\x80-\xff\000-\010\012-\037] *            #  more "normal"
+)*
+<
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+# <
+(?:
+@
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+(?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|
+\[                            # [
+(?: [^\\\x80-\xff\n\015\[\]] |  \\ [^\x80-\xff]  )*     #    stuff
+\]                           #           ]
+)
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+# optional trailing comments
+(?:
+\.
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+(?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|
+\[                            # [
+(?: [^\\\x80-\xff\n\015\[\]] |  \\ [^\x80-\xff]  )*     #    stuff
+\]                           #           ]
+)
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+# optional trailing comments
+)*
+(?: ,
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+@
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+(?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|
+\[                            # [
+(?: [^\\\x80-\xff\n\015\[\]] |  \\ [^\x80-\xff]  )*     #    stuff
+\]                           #           ]
+)
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+# optional trailing comments
+(?:
+\.
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+(?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|
+\[                            # [
+(?: [^\\\x80-\xff\n\015\[\]] |  \\ [^\x80-\xff]  )*     #    stuff
+\]                           #           ]
+)
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+# optional trailing comments
+)*
+)*  # additional domains
+:
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+# optional trailing comments
+)?     #       optional route
+(?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+# Atom
+|                       #  or
+"                                     # "
+[^\\\x80-\xff\n\015"] *                            #   normal
+(?:  \\ [^\x80-\xff]  [^\\\x80-\xff\n\015"] * )*        #   ( special normal* )*
+"                                     #        "
+# Quoted string
+)
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+(?:
+\.
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+(?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+# Atom
+|                       #  or
+"                                     # "
+[^\\\x80-\xff\n\015"] *                            #   normal
+(?:  \\ [^\x80-\xff]  [^\\\x80-\xff\n\015"] * )*        #   ( special normal* )*
+"                                     #        "
+# Quoted string
+)
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+# additional words
+)*
+@
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+(?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|
+\[                            # [
+(?: [^\\\x80-\xff\n\015\[\]] |  \\ [^\x80-\xff]  )*     #    stuff
+\]                           #           ]
+)
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+# optional trailing comments
+(?:
+\.
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+(?:
+[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+    # some number of atom characters...
+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom
+|
+\[                            # [
+(?: [^\\\x80-\xff\n\015\[\]] |  \\ [^\x80-\xff]  )*     #    stuff
+\]                           #           ]
+)
+[\040\t]*                    # Nab whitespace.
+(?:
+\(                              #  (
+[^\\\x80-\xff\n\015()] *                             #     normal*
+(?:                                 #       (
+(?:  \\ [^\x80-\xff]  |
+\(                            #  (
+[^\\\x80-\xff\n\015()] *                            #     normal*
+(?:  \\ [^\x80-\xff]   [^\\\x80-\xff\n\015()] * )*        #     (special normal*)*
+\)                           #                       )
+)    #         special
+[^\\\x80-\xff\n\015()] *                         #         normal*
+)*                                  #            )*
+\)                             #                )
+[\040\t]* )*    # If comment found, allow more spaces.
+# optional trailing comments
+)*
+#       address spec
+>                    #                 >
+# name and address
+)
+/x
+    Alan Other <user\@dom.ain>
+ 0: Alan Other <user@dom.ain>
+    <user\@dom.ain>
+ 0: user@dom.ain
+    user\@dom.ain
+ 0: user@dom.ain
+    \"A. Other\" <user.1234\@dom.ain> (a comment)
+ 0: "A. Other" <user.1234@dom.ain>
+    A. Other <user.1234\@dom.ain> (a comment)
+ 0:  Other <user.1234@dom.ain>
+    \"/s=user/ou=host/o=place/prmd=uu.yy/admd= /c=gb/\"\@x400-re.lay
+ 0: "/s=user/ou=host/o=place/prmd=uu.yy/admd= /c=gb/"@x400-re.lay
+    A missing angle <user\@some.where
+ 0: user@some.where
+    *** Failers
+No match
+    The quick brown fox
+No match
+
+/abc\0def\00pqr\000xyz\0000AB/
+    abc\0def\00pqr\000xyz\0000AB
+ 0: abc\x00def\x00pqr\x00xyz\x000AB
+    abc456 abc\0def\00pqr\000xyz\0000ABCDE
+ 0: abc\x00def\x00pqr\x00xyz\x000AB
+
+/abc\x0def\x00pqr\x000xyz\x0000AB/
+    abc\x0def\x00pqr\x000xyz\x0000AB
+ 0: abc\x0def\x00pqr\x000xyz\x0000AB
+    abc456 abc\x0def\x00pqr\x000xyz\x0000ABCDE
+ 0: abc\x0def\x00pqr\x000xyz\x0000AB
+
+/^[\000-\037]/
+    \0A
+ 0: \x00
+    \01B
+ 0: \x01
+    \037C
+ 0: \x1f
+
+/\0*/
+    \0\0\0\0
+ 0: \x00\x00\x00\x00
+
+/A\x0{2,3}Z/
+    The A\x0\x0Z
+ 0: A\x00\x00Z
+    An A\0\x0\0Z
+ 0: A\x00\x00\x00Z
+    *** Failers
+No match
+    A\0Z
+No match
+    A\0\x0\0\x0Z
+No match
+
+/^(cow|)\1(bell)/
+    cowcowbell
+ 0: cowcowbell
+ 1: cow
+ 2: bell
+    bell
+ 0: bell
+ 1: 
+ 2: bell
+    *** Failers
+No match
+    cowbell
+No match
+
+/^\s/
+    \040abc
+ 0:  
+    \x0cabc
+ 0: \x0c
+    \nabc
+ 0: \x0a
+    \rabc
+ 0: \x0d
+    \tabc
+ 0: \x09
+    *** Failers
+No match
+    abc
+No match
+
+/^a	b
+  
    c/x
+    abc
+ 0: abc
+
+/^(a|)\1*b/
+    ab
+ 0: ab
+ 1: a
+    aaaab
+ 0: aaaab
+ 1: a
+    b
+ 0: b
+ 1: 
+    *** Failers
+No match
+    acb
+No match
+
+/^(a|)\1+b/
+    aab
+ 0: aab
+ 1: a
+    aaaab
+ 0: aaaab
+ 1: a
+    b
+ 0: b
+ 1: 
+    *** Failers
+No match
+    ab
+No match
+
+/^(a|)\1?b/
+    ab
+ 0: ab
+ 1: a
+    aab
+ 0: aab
+ 1: a
+    b
+ 0: b
+ 1: 
+    *** Failers
+No match
+    acb
+No match
+
+/^(a|)\1{2}b/
+    aaab
+ 0: aaab
+ 1: a
+    b
+ 0: b
+ 1: 
+    *** Failers
+No match
+    ab
+No match
+    aab
+No match
+    aaaab
+No match
+
+/^(a|)\1{2,3}b/
+    aaab
+ 0: aaab
+ 1: a
+    aaaab
+ 0: aaaab
+ 1: a
+    b
+ 0: b
+ 1: 
+    *** Failers
+No match
+    ab
+No match
+    aab
+No match
+    aaaaab
+No match
+
+/ab{1,3}bc/
+    abbbbc
+ 0: abbbbc
+    abbbc
+ 0: abbbc
+    abbc
+ 0: abbc
+    *** Failers
+No match
+    abc
+No match
+    abbbbbc
+No match
+
+/([^.]*)\.([^:]*):[T ]+(.*)/
+    track1.title:TBlah blah blah
+ 0: track1.title:TBlah blah blah
+ 1: track1
+ 2: title
+ 3: Blah blah blah
+
+/([^.]*)\.([^:]*):[T ]+(.*)/i
+    track1.title:TBlah blah blah
+ 0: track1.title:TBlah blah blah
+ 1: track1
+ 2: title
+ 3: Blah blah blah
+
+/([^.]*)\.([^:]*):[t ]+(.*)/i
+    track1.title:TBlah blah blah
+ 0: track1.title:TBlah blah blah
+ 1: track1
+ 2: title
+ 3: Blah blah blah
+
+/^[W-c]+$/
+    WXY_^abc
+ 0: WXY_^abc
+    ***Failers
+No match
+    wxy
+No match
+
+/^[W-c]+$/i
+    WXY_^abc
+ 0: WXY_^abc
+    wxy_^ABC
+ 0: wxy_^ABC
+
+/^[\x3f-\x5F]+$/i
+    WXY_^abc
+ 0: WXY_^abc
+    wxy_^ABC
+ 0: wxy_^ABC
+
+/^abc$/m
+    abc
+ 0: abc
+    qqq\nabc
+ 0: abc
+    abc\nzzz
+ 0: abc
+    qqq\nabc\nzzz
+ 0: abc
+
+/^abc$/
+    abc
+ 0: abc
+    *** Failers
+No match
+    qqq\nabc
+No match
+    abc\nzzz
+No match
+    qqq\nabc\nzzz
+No match
+
+/\Aabc\Z/m
+    abc
+ 0: abc
+    *** Failers
+No match
+    qqq\nabc
+No match
+    abc\nzzz
+No match
+    qqq\nabc\nzzz
+No match
+
+/\A(.)*\Z/s
+    abc\ndef
+ 0: abc\x0adef
+ 1: f
+
+/\A(.)*\Z/m
+    *** Failers
+ 0: *** Failers
+ 1: s
+    abc\ndef
+No match
+
+/(?:b)|(?::+)/
+    b::c
+ 0: b
+    c::b
+ 0: ::
+
+/[-az]+/
+    az-
+ 0: az-
+    *** Failers
+ 0: a
+    b
+No match
+
+/[az-]+/
+    za-
+ 0: za-
+    *** Failers
+ 0: a
+    b
+No match
+
+/[a\-z]+/
+    a-z
+ 0: a-z
+    *** Failers
+ 0: a
+    b
+No match
+
+/[a-z]+/
+    abcdxyz
+ 0: abcdxyz
+
+/[\d-]+/
+    12-34
+ 0: 12-34
+    *** Failers
+No match
+    aaa
+No match
+
+/[\d-z]+/
+    12-34z
+ 0: 12-34z
+    *** Failers
+No match
+    aaa
+No match
+
+/\x5c/
+    \\
+ 0: \
+
+/\x20Z/
+    the Zoo
+ 0:  Z
+    *** Failers
+No match
+    Zulu
+No match
+
+/(abc)\1/i
+    abcabc
+ 0: abcabc
+ 1: abc
+    ABCabc
+ 0: ABCabc
+ 1: ABC
+    abcABC
+ 0: abcABC
+ 1: abc
+
+/(main(OPT)?)+/
+    mainmain
+ 0: mainmain
+ 1: main
+    mainOPTmain
+ 0: mainOPTmain
+ 1: main
+ 2: OPT
+
+/ab{3cd/
+    ab{3cd
+ 0: ab{3cd
+
+/ab{3,cd/
+    ab{3,cd
+ 0: ab{3,cd
+
+/ab{3,4a}cd/
+    ab{3,4a}cd
+ 0: ab{3,4a}cd
+
+/{4,5a}bc/
+    {4,5a}bc
+ 0: {4,5a}bc
+
+/^a.b/
+    a\rb
+ 0: a\x0db
+    *** Failers
+No match
+    a\nb
+No match
+
+/abc$/
+    abc
+ 0: abc
+    abc\n
+ 0: abc
+    *** Failers
+No match
+    abc\ndef
+No match
+
+/(abc)\123/
+    abc\x53
+ 0: abcS
+ 1: abc
+
+/(abc)\223/
+    abc\x93
+ 0: abc\x93
+ 1: abc
+
+/(abc)\323/
+    abc\xd3
+ 0: abc\xd3
+ 1: abc
+
+/(abc)\500/
+    abc\x40
+ 0: abc@
+ 1: abc
+    abc\100
+ 0: abc@
+ 1: abc
+
+/(abc)\5000/
+    abc\x400
+ 0: abc@0
+ 1: abc
+    abc\x40\x30
+ 0: abc@0
+ 1: abc
+    abc\1000
+ 0: abc@0
+ 1: abc
+    abc\100\x30
+ 0: abc@0
+ 1: abc
+    abc\100\060
+ 0: abc@0
+ 1: abc
+    abc\100\60
+ 0: abc@0
+ 1: abc
+
+/abc\81/
+   abc\081
+ 0: abc\x0081
+   abc\0\x38\x31
+ 0: abc\x0081
+
+/abc\91/
+   abc\091
+ 0: abc\x0091
+   abc\0\x39\x31
+ 0: abc\x0091
+
+/(a)(b)(c)(d)(e)(f)(g)(h)(i)(j)(k)(l)\12\123/
+    abcdefghijkllS
+ 0: abcdefghijkllS
+ 1: a
+ 2: b
+ 3: c
+ 4: d
+ 5: e
+ 6: f
+ 7: g
+ 8: h
+ 9: i
+10: j
+11: k
+12: l
+
+/(a)(b)(c)(d)(e)(f)(g)(h)(i)(j)(k)\12\123/
+    abcdefghijk\12S
+ 0: abcdefghijk\x0aS
+ 1: a
+ 2: b
+ 3: c
+ 4: d
+ 5: e
+ 6: f
+ 7: g
+ 8: h
+ 9: i
+10: j
+11: k
+
+/ab\gdef/
+    abgdef
+ 0: abgdef
+
+/a{0}bc/
+    bc
+ 0: bc
+
+/(a|(bc)){0,0}?xyz/
+    xyz
+ 0: xyz
+
+/abc[\10]de/
+    abc\010de
+ 0: abc\x08de
+
+/abc[\1]de/
+    abc\1de
+ 0: abc\x01de
+
+/(abc)[\1]de/
+    abc\1de
+ 0: abc\x01de
+ 1: abc
+
+/a.b(?s)/
+    a\nb
+ 0: a\x0ab
+
+/^([^a])([^\b])([^c]*)([^d]{3,4})/
+    baNOTccccd
+ 0: baNOTcccc
+ 1: b
+ 2: a
+ 3: NOT
+ 4: cccc
+    baNOTcccd
+ 0: baNOTccc
+ 1: b
+ 2: a
+ 3: NOT
+ 4: ccc
+    baNOTccd
+ 0: baNOTcc
+ 1: b
+ 2: a
+ 3: NO
+ 4: Tcc
+    bacccd
+ 0: baccc
+ 1: b
+ 2: a
+ 3: 
+ 4: ccc
+    *** Failers
+ 0: *** Failers
+ 1: *
+ 2: *
+ 3: * Fail
+ 4: ers
+    anything
+No match
+    b\bc   
+No match
+    baccd
+No match
+
+/[^a]/
+  Abc
+ 0: A
+  
+/[^a]/i
+  Abc 
+ 0: b
+
+/[^a]+/
+  AAAaAbc
+ 0: AAA
+  
+/[^a]+/i
+  AAAaAbc 
+ 0: bc
+
+/[^a]+/
+   bbb\nccc
+ 0: bbb\x0accc
+
+/ End of test input /
+
diff --git a/testoutput2 b/testoutput2
new file mode 100644
index 0000000..ec09561
--- /dev/null
+++ b/testoutput2
@@ -0,0 +1,573 @@
+Testing Perl-Compatible Regular Expressions
+PCRE version 1.00 18-Nov-1997
+
+/(a)b|/
+Identifying subpattern count = 1
+No options
+No first char
+
+/(a*)*/
+Failed: operand of unlimited repeat could match the empty string at offset 4
+
+/(abc|)+/
+Failed: operand of unlimited repeat could match the empty string at offset 6
+
+/abc/
+Identifying subpattern count = 0
+No options
+First char = 'a'
+    abc
+ 0: abc
+    defabc
+ 0: abc
+    \Aabc
+ 0: abc
+    \IABC
+ 0: ABC
+    *** Failers
+No match
+    \Adefabc
+No match
+    ABC
+No match
+
+/^abc/
+Identifying subpattern count = 0
+Options: anchored
+No first char
+    abc
+ 0: abc
+    \Aabc
+ 0: abc
+    *** Failers
+No match
+    defabc
+No match
+    \Adefabc
+No match
+
+/a+bc/
+Identifying subpattern count = 0
+No options
+First char = 'a'
+
+/a*bc/
+Identifying subpattern count = 0
+No options
+No first char
+
+/a{3}bc/
+Identifying subpattern count = 0
+No options
+First char = 'a'
+
+/(abc|a+z)/
+Identifying subpattern count = 1
+No options
+First char = 'a'
+
+/^abc$/
+Identifying subpattern count = 0
+Options: anchored
+No first char
+    abc
+ 0: abc
+    \Mdef\nabc
+ 0: abc
+    *** Failers
+No match
+    def\nabc
+No match
+
+/abc\/
+Failed: \ at end of pattern at offset 4
+
+/ab\gdef/X
+Failed: unrecognized character follows \ at offset 3
+
+/x{5,4}/
+Failed: numbers out of order in {} quantifier at offset 5
+
+/z{65536}/
+Failed: number too big in {} quantifier at offset 7
+
+/[abcd/
+Failed: missing terminating ] for character class at offset 5
+
+/[\B]/
+Failed: invalid escape sequence in character class at offset 2
+
+/[a-\w]/
+Failed: invalid escape sequence in character class at offset 4
+
+/[z-a]/
+Failed: range out of order in character class at offset 3
+
+/^*/
+Failed: nothing to repeat at offset 1
+
+/(abc/
+Failed: missing ) at offset 4
+
+/(?# abc/
+Failed: missing ) after comment at offset 7
+
+/(?z)abc/
+Failed: unrecognized character after (? at offset 2
+
+/.*b/
+Identifying subpattern count = 0
+Options: anchored
+No first char
+
+/.*?b/
+Identifying subpattern count = 0
+Options: anchored
+No first char
+
+/cat|dog|elephant/
+Identifying subpattern count = 0
+No options
+No first char
+    this sentence eventually mentions a cat
+ 0: cat
+    this sentences rambles on and on for a while and then reaches elephant
+ 0: elephant
+
+/cat|dog|elephant/S
+Identifying subpattern count = 0
+No options
+No first char
+Starting character set: c d e 
+    this sentence eventually mentions a cat
+ 0: cat
+    this sentences rambles on and on for a while and then reaches elephant
+ 0: elephant
+
+/cat|dog|elephant/iS
+Identifying subpattern count = 0
+Options: caseless
+No first char
+Starting character set: C D E c d e 
+    this sentence eventually mentions a CAT cat
+ 0: CAT
+    this sentences rambles on and on for a while to elephant ElePhant
+ 0: elephant
+
+/cat|dog|elephant/IS
+Identifying subpattern count = 0
+No options
+No first char
+Starting character set: C D E c d e 
+    this sentence eventually mentions a CAT cat
+ 0: cat
+    this sentences rambles on and on for a while to elephant ElePhant
+ 0: elephant
+
+/cat|dog|elephant/IS
+Identifying subpattern count = 0
+No options
+No first char
+Starting character set: C D E c d e 
+    \Ithis sentence eventually mentions a CAT cat
+ 0: CAT
+    \Ithis sentences rambles on and on for a while to elephant ElePhant
+ 0: elephant
+
+/a|[bcd]/S
+Identifying subpattern count = 0
+No options
+No first char
+Starting character set: a b c d 
+
+/(a|[^\dZ])/S
+Identifying subpattern count = 1
+No options
+No first char
+Starting character set: \x00 \x01 \x02 \x03 \x04 \x05 \x06 \x07 \x08 \x09 \x0a 
+  \x0b \x0c \x0d \x0e \x0f \x10 \x11 \x12 \x13 \x14 \x15 \x16 \x17 \x18 \x19 
+  \x1a \x1b \x1c \x1d \x1e \x1f \x20 ! " # $ % & ' ( ) * + , - . / : ; < = > 
+  ? @ A B C D E F G H I J K L M N O P Q R S T U V W X Y [ \ ] ^ _ ` a b c d 
+  e f g h i j k l m n o p q r s t u v w x y z { | } ~ \x7f \x80 \x81 \x82 \x83 
+  \x84 \x85 \x86 \x87 \x88 \x89 \x8a \x8b \x8c \x8d \x8e \x8f \x90 \x91 \x92 
+  \x93 \x94 \x95 \x96 \x97 \x98 \x99 \x9a \x9b \x9c \x9d \x9e \x9f \xa0 \xa1 
+  \xa2 \xa3 \xa4 \xa5 \xa6 \xa7 \xa8 \xa9 \xaa \xab \xac \xad \xae \xaf \xb0 
+  \xb1 \xb2 \xb3 \xb4 \xb5 \xb6 \xb7 \xb8 \xb9 \xba \xbb \xbc \xbd \xbe \xbf 
+  \xc0 \xc1 \xc2 \xc3 \xc4 \xc5 \xc6 \xc7 \xc8 \xc9 \xca \xcb \xcc \xcd \xce 
+  \xcf \xd0 \xd1 \xd2 \xd3 \xd4 \xd5 \xd6 \xd7 \xd8 \xd9 \xda \xdb \xdc \xdd 
+  \xde \xdf \xe0 \xe1 \xe2 \xe3 \xe4 \xe5 \xe6 \xe7 \xe8 \xe9 \xea \xeb \xec 
+  \xed \xee \xef \xf0 \xf1 \xf2 \xf3 \xf4 \xf5 \xf6 \xf7 \xf8 \xf9 \xfa \xfb 
+  \xfc \xfd \xfe \xff 
+
+/(a|b)*[\s]/S
+Identifying subpattern count = 1
+No options
+No first char
+Starting character set: \x09 \x0a \x0b \x0c \x0d \x20 a b 
+
+/(ab\2)/
+Failed: back reference to non-existent subpattern at offset 4
+
+/{4,5}abc/
+Failed: nothing to repeat at offset 4
+
+/(a)(b)(c)\2/
+Identifying subpattern count = 3
+No options
+First char = 'a'
+    abcb
+ 0: abcb
+ 1: a
+ 2: b
+ 3: c
+    \O0abcb
+Matched, but too many substrings
+    \O2abcb
+Matched, but too many substrings
+ 0: abcb
+    \O4abcb
+Matched, but too many substrings
+ 0: abcb
+ 1: a
+    \O6abcb
+Matched, but too many substrings
+ 0: abcb
+ 1: a
+ 2: b
+    \O8abcb
+ 0: abcb
+ 1: a
+ 2: b
+ 3: c
+
+/(a)bc|(a)(b)\2/
+Identifying subpattern count = 3
+No options
+First char = 'a'
+    abc
+ 0: abc
+ 1: a
+    \O0abc
+Matched, but too many substrings
+    \O2abc
+Matched, but too many substrings
+ 0: abc
+    \O4abc
+ 0: abc
+ 1: a
+    aba
+ 0: aba
+ 1: <unset>
+ 2: a
+ 3: b
+    \O0aba
+Matched, but too many substrings
+    \O2aba
+Matched, but too many substrings
+ 0: aba
+    \O4aba
+Matched, but too many substrings
+ 0: aba
+ 1: <unset>
+    \O6aba
+Matched, but too many substrings
+ 0: aba
+ 1: <unset>
+ 2: a
+    \O8aba
+ 0: aba
+ 1: <unset>
+ 2: a
+ 3: b
+
+/^a.b/
+Identifying subpattern count = 0
+Options: anchored
+No first char
+    \Sa\nb
+ 0: a\x0ab
+
+/abc$/E
+Identifying subpattern count = 0
+Options: dollar_endonly
+First char = 'a'
+    abc
+ 0: abc
+    *** Failers
+No match
+    abc\n
+No match
+    abc\ndef
+No match
+
+/abc$/
+Identifying subpattern count = 0
+No options
+First char = 'a'
+    *** Failers
+No match
+    \Eabc\n
+No match
+    \Eabc\ndef
+No match
+
+/abc$/m
+Identifying subpattern count = 0
+Options: multiline
+First char = 'a'
+    \Eabc\n
+ 0: abc
+    \Eabc\ndef
+ 0: abc
+
+/(a)(b)(c)(d)(e)\6/
+Failed: back reference to non-existent subpattern at offset 16
+
+/the quick brown fox/
+Identifying subpattern count = 0
+No options
+First char = 't'
+    the quick brown fox
+ 0: the quick brown fox
+    this is a line with the quick brown fox
+ 0: the quick brown fox
+
+/the quick brown fox/A
+Identifying subpattern count = 0
+Options: anchored
+No first char
+    the quick brown fox
+ 0: the quick brown fox
+    *** Failers
+No match
+    this is a line with the quick brown fox
+No match
+
+/ab(?z)cd/
+Failed: unrecognized character after (? at offset 4
+
+".*/\Xfoo"X
+Identifying subpattern count = 0
+Options: anchored extra
+No first char
+    /this/is/a/very/long/line/in/deed/with/very/many/slashes/in/it/you/see/
+No match
+
+".*/\Xfoo"X
+Identifying subpattern count = 0
+Options: anchored extra
+No first char
+    /this/is/a/very/long/line/in/deed/with/very/many/slashes/in/and/foo
+ 0: /this/is/a/very/long/line/in/deed/with/very/many/slashes/in/and/foo
+
+/(\.\d\d[1-9]?)\d+/
+Identifying subpattern count = 1
+No options
+First char = '.'
+    1.230003938
+ 0: .230003938
+ 1: .23
+    1.875000282
+ 0: .875000282
+ 1: .875
+    1.235 
+ 0: .235
+ 1: .23
+
+/(\.\d\d[1-9]?)\X\d+/X
+Identifying subpattern count = 1
+Options: extra
+First char = '.'
+    1.230003938
+ 0: .230003938
+ 1: .23
+    1.875000282
+ 0: .875000282
+ 1: .875
+    *** Failers 
+No match
+    1.235 
+No match
+
+/(\.\d\d((?=0)|\d(?=\d)))/
+Identifying subpattern count = 2
+No options
+First char = '.'
+    1.230003938
+ 0: .23
+ 1: .23
+ 2: 
+    1.875000282
+ 0: .875
+ 1: .875
+ 2: 5
+    *** Failers 
+No match
+    1.235 
+No match
+
+/^(\w+\X|\s+\X)*$/X
+Identifying subpattern count = 1
+Options: anchored extra
+No first char
+    now is the time for all good men to come to the aid of the party
+ 0: now is the time for all good men to come to the aid of the party
+ 1: party
+    *** Failers
+No match
+    this is not a line with only words and spaces!
+No match
+    
+/^abc|def/
+Identifying subpattern count = 0
+No options
+No first char
+    abcdef
+ 0: abc
+    abcdef\B
+ 0: def
+
+/.*((abc)$|(def))/
+Identifying subpattern count = 3
+Options: anchored
+No first char
+    defabc
+ 0: defabc
+ 1: abc
+ 2: abc
+    \Zdefabc
+ 0: def
+ 1: def
+ 2: <unset>
+ 3: def
+
+/abc/P
+    abc
+ 0: abc
+    *** Failers
+No match: POSIX code 17: match failed
+    
+/^abc|def/P
+    abcdef
+ 0: abc
+    abcdef\B
+ 0: def
+
+/.*((abc)$|(def))/P
+    defabc
+ 0: defabc
+ 1: abc
+ 2: abc
+    \Zdefabc
+ 0: def
+ 1: def
+ 3: def
+  
+/the quick brown fox/P
+    the quick brown fox
+ 0: the quick brown fox
+    *** Failers 
+No match: POSIX code 17: match failed
+    The Quick Brown Fox 
+No match: POSIX code 17: match failed
+
+/the quick brown fox/Pi
+    the quick brown fox
+ 0: the quick brown fox
+    The Quick Brown Fox 
+ 0: The Quick Brown Fox
+
+/abc.def/P
+    *** Failers
+No match: POSIX code 17: match failed
+    abc\ndef
+No match: POSIX code 17: match failed
+    
+/abc$/P
+    abc
+ 0: abc
+    abc\n 
+ 0: abc
+
+/abc\/P
+Failed: POSIX code 9: bad escape sequence at offset 4     
+
+/(abc)\2/P
+Failed: POSIX code 15: bad back reference at offset 6     
+
+/(abc\1)/P
+    abc
+No match: POSIX code 15: bad back reference
+
+"(?>.*/)foo"X
+Identifying subpattern count = 0
+Options: anchored extra
+No first char
+    /this/is/a/very/long/line/in/deed/with/very/many/slashes/in/it/you/see/
+No match
+
+"(?>.*/)foo"X
+Identifying subpattern count = 0
+Options: anchored extra
+No first char
+    /this/is/a/very/long/line/in/deed/with/very/many/slashes/in/and/foo
+ 0: /this/is/a/very/long/line/in/deed/with/very/many/slashes/in/and/foo
+
+/(?>(\.\d\d[1-9]?))\d+/X
+Identifying subpattern count = 1
+Options: extra
+No first char
+    1.230003938
+ 0: .230003938
+ 1: .23
+    1.875000282
+ 0: .875000282
+ 1: .875
+    *** Failers 
+No match
+    1.235 
+No match
+
+/^((?>\w+)|(?>\s+))*$/X
+Identifying subpattern count = 1
+Options: anchored extra
+No first char
+    now is the time for all good men to come to the aid of the party
+ 0: now is the time for all good men to come to the aid of the party
+ 1: party
+    *** Failers
+No match
+    this is not a line with only words and spaces!
+No match
+    
+/(\d+)(\w)/X
+Identifying subpattern count = 2
+Options: extra
+No first char
+    12345a
+ 0: 12345a
+ 1: 12345
+ 2: a
+    12345+ 
+ 0: 12345
+ 1: 1234
+ 2: 5
+
+/((?>\d+))(\w)/X
+Identifying subpattern count = 2
+Options: extra
+No first char
+    12345a
+ 0: 12345a
+ 1: 12345
+ 2: a
+    *** Failers
+No match
+    12345+ 
+No match
+
+/ End of test input /
+Identifying subpattern count = 0
+No options
+First char = ' '
+