perl 5.003_03: dev/null

New file describing all the config.sh variables.
Eventually, I hope to fill this directory with other useful
stuff.

1 files changed, 1329 insertions, 0 deletions

diff --git a/Porting/Glossary b/Porting/Glossary
new file mode 100644
index 0000000000..f1d3e97007
--- /dev/null
+++ b/Porting/Glossary
@@ -0,0 +1,1329 @@
+This file contains a description of all the shell variables whose value is
+determined by the Configure script.  Variables intended for use in C
+programs (e.g. I_UNISTD) are already described in config_h.SH.
+
+alignbytes (alignbytes.U):
+	This variable holds the number of bytes required to align a
+	double. Usual values are 2, 4 and 8.
+
+ar (Unix.U):
+	This variable defines the command to use to create an archive 
+	library.  For unix, it is 'ar'.
+
+archlib (archlib.U):
+	This variable holds the name of the directory in which the user wants
+	to put architecture-dependent public library files for $package.
+	It is most often a local directory such as /usr/local/lib.
+	Programs using this variable must be prepared to deal
+	with filename expansion.
+
+archlibexp (archlib.U):
+	This variable is the same as the archlib variable, but is
+	filename expanded at configuration time, for convenient use.
+
+archobjs (Unix.U):
+	This variable defines any additional objects that must be linked
+	in with the program on this architecture.  On unix, it is usually
+	empty.  It is typically used to include emulations of unix calls
+	or other facilities.  For perl on OS/2, for example, this would
+	include os2/os2.obj.
+
+bin (bin.U):
+	This variable holds the name of the directory in which the user wants
+	to put publicly executable images for the package in question.  It
+	is most often a local directory such as /usr/local/bin. Programs using
+	this variable must be prepared to deal with ~name substitution.
+
+byteorder (byteorder.U):
+	This variable holds the byte order. In the following, larger digits
+	indicate more significance.  The variable byteorder is either 4321
+	on a big-endian machine, or 1234 on a little-endian, or 87654321
+	on a Cray ... or 3412 with weird order !
+
+c (n.U):
+	This variable contains the \c string if that is what causes the echo
+	command to suppress newline.  Otherwise it is null.  Correct usage is
+	    $echo $n "prompt for a question: $c".
+
+castflags (d_castneg.U):
+	This variable contains a flag that precise difficulties the
+	compiler has casting odd floating values to unsigned long:
+		0 = ok
+		1 = couldn't cast < 0
+		2 = couldn't cast >= 0x80000000
+		4 = couldn't cast in argument expression list
+
+cc (cc.U):
+	This variable holds the name of a command to execute a C compiler which
+	can resolve multiple global references that happen to have the same
+	name.  Usual values are "cc", "Mcc", "cc -M", and "gcc".
+
+cccdlflags (dlsrc.U):
+	This variable contains any special flags that might need to be
+	passed with cc -c to compile modules to be used to create a shared
+	library that will be used for dynamic loading.  For hpux, this 
+	should be +z.  It is up to the makefile to use it.
+
+ccdlflags (dlsrc.U):
+	This variable contains any special flags that might need to be
+	passed to cc to link with a shared library for dynamic loading. 
+	It is up to the makefile to use it.  For sunos 4.1, it should
+	be empty.
+
+ccflags (ccflags.U):
+	This variable contains any additional C compiler flags desired by
+	the user.  It is up to the Makefile to use this.
+
+cf_by (cf_who.U):
+	Login name of the person who ran the Configure script and answered the
+	questions. This is used to tag both config.sh and config_h.SH.
+
+cf_time (cf_who.U):
+	Holds the output of the "date" command when the configuration file was
+	produced. This is used to tag both config.sh and config_h.SH.
+
+cpp_stuff (cpp_stuff.U):
+	This variable contains an identification of the catenation mechanism
+	used by the C preprocessor.
+
+cppflags (ccflags.U):
+	This variable holds the flags that will be passed to the C pre-
+	processor. It is up to the Makefile to use it.
+
+cppminus (cppstdin.U):
+	This variable contains the second part of the string which will invoke
+	the C preprocessor on the standard input and produce to standard
+	output.  This variable will have the value "-" if cppstdin needs a minus
+	to specify standard input, otherwise the value is "".
+
+cppstdin (cppstdin.U):
+	This variable contains the command which will invoke the C
+	preprocessor on standard input and put the output to stdout.
+	It is primarily used by other Configure units that ask about
+	preprocessor symbols.
+
+cryptlib (d_crypt.U):
+	This variable holds -lcrypt or the path to a libcrypt.a archive if
+	the crypt() function is not defined in the standard C library. It is
+	up to the Makefile to use this.
+
+d_Gconvert (d_gconvert.U):
+	This variable holds what Gconvert is defined as to convert
+	floating point numbers into strings. It could be 'gconvert'
+	or a more complex macro emulating gconvert with gcvt() or sprintf.
+
+d_access (d_access.U):
+	This variable conditionally defines HAS_ACCESS if the access() system
+	call is available to check for access permissions using real IDs.
+
+d_alarm (d_alarm.U):
+	This variable conditionally defines the HAS_ALARM symbol, which
+	indicates to the C program that the alarm() routine is available.
+
+d_archlib (archlib.U):
+	This variable conditionally defines ARCHLIB to hold the pathname
+	of architecture-dependent library files for $package.  If
+	$archlib is the same as $privlib, then this is set to undef.
+
+d_bcmp (d_bcmp.U):
+	This variable conditionally defines the HAS_BCMP symbol if
+	the bcmp() routine is available to compare strings.
+
+d_bcopy (d_bcopy.U):
+	This variable conditionally defines the HAS_BCOPY symbol if
+	the bcopy() routine is available to copy strings.
+
+d_bsdpgrp (d_setpgrp.U):
+	This variable conditionally defines USE_BSDPGRP if the notion of
+	process group is the BSD one. This means setpgrp needs two arguments
+	whereas USG one needs none.
+
+d_bzero (d_bzero.U):
+	This variable conditionally defines the HAS_BZERO symbol if
+	the bzero() routine is available to set memory to 0.
+
+d_casti32 (d_casti32.U):
+	This variable conditionally defines CASTI32, which indicates
+	whether the C compiler can cast large floats to 32-bit ints.
+
+d_castneg (d_castneg.U):
+	This variable conditionally defines CASTNEG, which indicates
+	wether the C compiler can cast negative float to unsigned.
+
+d_charvspr (d_vprintf.U):
+	This variable conditionally defines CHARVSPRINTF if this system
+	has vsprintf returning type (char*).  The trend seems to be to
+	declare it as "int vsprintf()".
+
+d_chown (d_chown.U):
+	This variable conditionally defines the HAS_CHOWN symbol, which
+	indicates to the C program that the chown() routine is available.
+
+d_chroot (d_chroot.U):
+	This variable conditionally defines the HAS_CHROOT symbol, which
+	indicates to the C program that the chroot() routine is available.
+
+d_chsize (d_chsize.U):
+	This variable conditionally defines the CHSIZE symbol, which
+	indicates to the C program that the chsize() routine is available
+	to truncate files.  You might need a -lx to get this routine.
+
+d_const (d_const.U):
+	This variable conditionally defines the HASCONST symbol, which
+	indicates to the C program that this C compiler knows about the
+	const type.
+
+d_crypt (d_crypt.U):
+	This variable conditionally defines the CRYPT symbol, which
+	indicates to the C program that the crypt() routine is available
+	to encrypt passwords and the like.
+
+d_csh (d_csh.U):
+	This variable conditionally defines the CSH symbol, which
+	indicates to the C program that the C-shell exists.
+
+d_cuserid (d_cuserid.U):
+	This variable conditionally defines the HAS_CUSERID symbol, which
+	indicates to the C program that the cuserid() routine is available
+	to get character login names.
+
+d_dbl_dig (d_dbl_dig.U):
+	This variable conditionally defines d_dbl_dig if this system's
+	header files provide DBL_DIG, which is the number of significant
+	digits in a double precision number.
+
+d_difftime (d_difftime.U):
+	This variable conditionally defines the HAS_DIFFTIME symbol, which
+	indicates to the C program that the difftime() routine is available.
+
+d_dirnamlen (i_dirent.U):
+	This variable conditionally defines DIRNAMLEN, which indicates
+	to the C program that the length of directory entry names is
+	provided by a d_namelen field.
+
+d_dlerror (d_dlerror.U):
+	This variable conditionally defines the HAS_DLERROR symbol, which
+	indicates to the C program that the dlerror() routine is available.
+
+d_dlsymun (d_dlsymun.U):
+	This variable conditionally defines DLSYM_NEEDS_UNDERSCORE, which
+	indicates that we need to prepend an underscore to the symbol
+	name before calling dlsym().
+
+d_dosuid (d_dosuid.U):
+	This variable conditionally defines the symbol DOSUID, which
+	tells the C program that it should insert setuid emulation code
+	on hosts which have setuid #! scripts disabled.
+
+d_dup2 (d_dup2.U):
+	This variable conditionally defines HAS_DUP2 if dup2() is
+	available to duplicate file descriptors.
+
+d_eofnblk (nblock_io.U):
+	This variable conditionally defines EOF_NONBLOCK if EOF can be seen
+	when reading from a non-blocking I/O source.
+
+d_fchmod (d_fchmod.U):
+	This variable conditionally defines the HAS_FCHMOD symbol, which
+	indicates to the C program that the fchmod() routine is available
+	to change mode of opened files.
+
+d_fchown (d_fchown.U):
+	This variable conditionally defines the HAS_FCHOWN symbol, which
+	indicates to the C program that the fchown() routine is available
+	to change ownership of opened files.
+
+d_fcntl (d_fcntl.U):
+	This variable conditionally defines the HAS_FCNTL symbol, and indicates
+	whether the fcntl() function exists
+
+d_fgetpos (d_fgetpos.U):
+	This variable conditionally defines HAS_FGETPOS if fgetpos() is
+	available to get the file position indicator.
+
+d_flexfnam (d_flexfnam.U):
+	This variable conditionally defines the FLEXFILENAMES symbol, which
+	indicates that the system supports filenames longer than 14 characters.
+
+d_flock (d_flock.U):
+	This variable conditionally defines HAS_FLOCK if flock() is
+	available to do file locking.
+
+d_fork (d_fork.U):
+	This variable conditionally defines the HAS_FORK symbol, which
+	indicates to the C program that the fork() routine is available.
+
+d_fpathconf (d_pathconf.U):
+	This variable conditionally defines the HAS_FPATHCONF symbol, which
+	indicates to the C program that the pathconf() routine is available
+	to determine file-system related limits and options associated
+	with a given open file descriptor.
+
+d_fsetpos (d_fsetpos.U):
+	This variable conditionally defines HAS_FSETPOS if fsetpos() is
+	available to set the file position indicator.
+
+d_gethent (d_gethent.U):
+	This variable conditionally defines HAS_GETHOSTENT if gethostent() is
+	available to dup file descriptors.
+
+d_getlogin (d_getlogin.U):
+	This variable conditionally defines the HAS_GETLOGIN symbol, which
+	indicates to the C program that the getlogin() routine is available
+	to get the login name.
+
+d_getpgrp (d_getpgrp.U):
+	This variable conditionally defines HAS_GETPGRP if getpgrp() is
+	available to get the current process group.
+
+d_getpgrp2 (d_getpgrp2.U):
+	This variable conditionally defines the HAS_GETPGRP2 symbol, which
+	indicates to the C program that the getpgrp2() (as in DG/UX) routine
+	is available to get the current process group.
+
+d_getppid (d_getppid.U):
+	This variable conditionally defines the HAS_GETPPID symbol, which
+	indicates to the C program that the getppid() routine is available
+	to get the parent process ID.
+
+d_getprior (d_getprior.U):
+	This variable conditionally defines HAS_GETPRIORITY if getpriority()
+	is available to get a process's priority.
+
+d_htonl (d_htonl.U):
+	This variable conditionally defines HAS_HTONL if htonl() and its
+	friends are available to do network order byte swapping.
+
+d_index (d_strchr.U):
+	This variable conditionally defines HAS_INDEX if index() and
+	rindex() are available for string searching.
+
+d_isascii (d_isascii.U):
+	This variable conditionally defines the HAS_ISASCII constant,
+	which indicates to the C program that isascii() is available.
+
+d_killpg (d_killpg.U):
+	This variable conditionally defines the HAS_KILLPG symbol, which
+	indicates to the C program that the killpg() routine is available
+	to kill process groups.
+
+d_link (d_link.U):
+	This variable conditionally defines HAS_LINK if link() is
+	available to create hard links.
+
+d_locconv (d_locconv.U):
+	This variable conditionally defines HAS_LOCALECONV if localeconv() is
+	available for numeric and monetary formatting conventions.
+
+d_lockf (d_lockf.U):
+	This variable conditionally defines HAS_LOCKF if lockf() is
+	available to do file locking.
+
+d_lstat (d_lstat.U):
+	This variable conditionally defines HAS_LSTAT if lstat() is
+	available to do file stats on symbolic links.
+
+d_mblen (d_mblen.U):
+	This variable conditionally defines the HAS_MBLEN symbol, which
+	indicates to the C program that the mblen() routine is available
+	to find the number of bytes in a multibye character.
+
+d_mbstowcs (d_mbstowcs.U):
+	This variable conditionally defines the HAS_MBSTOWCS symbol, which
+	indicates to the C program that the mbstowcs() routine is available
+	to convert a multibyte string into a wide character string.
+
+d_mbtowc (d_mbtowc.U):
+	This variable conditionally defines the HAS_MBTOWC symbol, which
+	indicates to the C program that the mbtowc() routine is available
+	to convert multibyte to a wide character.
+
+d_memcmp (d_memcmp.U):
+	This variable conditionally defines the HAS_MEMCMP symbol, which
+	indicates to the C program that the memcmp() routine is available
+	to compare blocks of memory.
+
+d_memcpy (d_memcpy.U):
+	This variable conditionally defines the HAS_MEMCPY symbol, which
+	indicates to the C program that the memcpy() routine is available
+	to copy blocks of memory.
+
+d_memmove (d_memmove.U):
+	This variable conditionally defines the HAS_MEMMOVE symbol, which
+	indicates to the C program that the memmove() routine is available
+	to copy potentatially overlapping blocks of memory.
+
+d_memset (d_memset.U):
+	This variable conditionally defines the HAS_MEMSET symbol, which
+	indicates to the C program that the memset() routine is available
+	to set blocks of memory.
+
+d_mkdir (d_mkdir.U):
+	This variable conditionally defines the HAS_MKDIR symbol, which
+	indicates to the C program that the mkdir() routine is available
+	to create directories..
+
+d_mkfifo (d_mkfifo.U):
+	This variable conditionally defines the HAS_MKFIFO symbol, which
+	indicates to the C program that the mkfifo() routine is available.
+
+d_mktime (d_mktime.U):
+	This variable conditionally defines the HAS_MKTIME symbol, which
+	indicates to the C program that the mktime() routine is available.
+
+d_msg (d_msg.U):
+	This variable conditionally defines the HAS_MSG symbol, which
+	indicates that the entire msg*(2) library is present.
+
+d_mymalloc (mallocsrc.U):
+	This variable conditionally defines MYMALLOC in case other parts
+	of the source want to take special action if MYMALLOC is used.
+	This may include different sorts of profiling or error detection.
+
+d_nice (d_nice.U):
+	This variable conditionally defines the HAS_NICE symbol, which
+	indicates to the C program that the nice() routine is available.
+
+d_oldarchlib (oldarchlib.U):
+	This variable conditionally defines OLDARCHLIB to hold the pathname
+	of architecture-dependent library files for a previous
+	version of $package.
+
+d_open3 (d_open3.U):
+	This variable conditionally defines the HAS_OPEN3 manifest constant,
+	which indicates to the C program that the 3 argument version of
+	the open(2) function is available.
+
+d_pathconf (d_pathconf.U):
+	This variable conditionally defines the HAS_PATHCONF symbol, which
+	indicates to the C program that the pathconf() routine is available
+	to determine file-system related limits and options associated
+	with a given filename.
+
+d_pause (d_pause.U):
+	This variable conditionally defines the HAS_PAUSE symbol, which
+	indicates to the C program that the pause() routine is available
+	to suspend a process until a signal is received.
+
+d_pipe (d_pipe.U):
+	This variable conditionally defines the HAS_PIPE symbol, which
+	indicates to the C program that the pipe() routine is available
+	to create an inter-process channel.
+
+d_poll (d_poll.U):
+	This variable conditionally defines the HAS_POLL symbol, which
+	indicates to the C program that the poll() routine is available
+	to poll active file descriptors.
+
+d_pwage (i_pwd.U):
+	This varaible conditionally defines PWAGE, which indicates
+	that struct passwd contains pw_age.
+
+d_pwchange (i_pwd.U):
+	This varaible conditionally defines PWCHANGE, which indicates
+	that struct passwd contains pw_change.
+
+d_pwclass (i_pwd.U):
+	This varaible conditionally defines PWCLASS, which indicates
+	that struct passwd contains pw_class.
+
+d_pwcomment (i_pwd.U):
+	This varaible conditionally defines PWCOMMENT, which indicates
+	that struct passwd contains pw_comment.
+
+d_pwexpire (i_pwd.U):
+	This varaible conditionally defines PWEXPIRE, which indicates
+	that struct passwd contains pw_expire.
+
+d_pwquota (i_pwd.U):
+	This varaible conditionally defines PWQUOTA, which indicates
+	that struct passwd contains pw_quota.
+
+d_readdir (d_readdir.U):
+	This variable conditionally defines HAS_READDIR if readdir() is
+	available to read directory entries.
+
+d_readlink (d_readlink.U):
+	This variable conditionally defines the HAS_READLINK symbol, which
+	indicates to the C program that the readlink() routine is available
+	to read the value of a symbolic link.
+
+d_rename (d_rename.U):
+	This variable conditionally defines the HAS_RENAME symbol, which
+	indicates to the C program that the rename() routine is available
+	to rename files.
+
+d_rewinddir (d_readdir.U):
+	This variable conditionally defines HAS_REWINDDIR if rewinddir() is
+	available.
+
+d_rmdir (d_rmdir.U):
+	This variable conditionally defines HAS_RMDIR if rmdir() is
+	available to remove directories.
+
+d_safebcpy (d_safebcpy.U):
+	This variable conditionally defines the HAS_SAFE_BCOPY symbol if
+	the bcopy() routine can do overlapping copies.
+
+d_safemcpy (d_safemcpy.U):
+	This variable conditionally defines the HAS_SAFE_MEMCPY symbol if
+	the memcpy() routine can do overlapping copies.
+
+d_seekdir (d_readdir.U):
+	This variable conditionally defines HAS_SEEKDIR if seekdir() is
+	available.
+
+d_select (d_select.U):
+	This variable conditionally defines HAS_SELECT if select() is
+	available to select active file descriptors. A <sys/time.h>
+	inclusion may be necessary for the timeout field.
+
+d_sem (d_sem.U):
+	This variable conditionally defines the HAS_SEM symbol, which
+	indicates that the entire sem*(2) library is present.
+
+d_setegid (d_setegid.U):
+	This variable conditionally defines the HAS_SETEGID symbol, which
+	indicates to the C program that the setegid() routine is available
+	to change the effective gid of the current program.
+
+d_seteuid (d_seteuid.U):
+	This variable conditionally defines the HAS_SETEUID symbol, which
+	indicates to the C program that the seteuid() routine is available
+	to change the effective uid of the current program.
+
+d_setlinebuf (d_setlnbuf.U):
+	This variable conditionally defines the HAS_SETLINEBUF symbol, which
+	indicates to the C program that the setlinebuf() routine is available
+	to change stderr or stdout from block-buffered or unbuffered to a
+	line-buffered mode.
+
+d_setlocale (d_setlocale.U):
+	This variable conditionally defines HAS_SETLOCALE if setlocale() is
+	available to handle locale-specific ctype implementations.
+
+d_setpgid (d_setpgid.U):
+	This variable conditionally defines HAS_SETPGID if setpgid() is
+	available to set process group ID.
+
+d_setpgrp (d_setpgrp.U):
+	This variable conditionally defines HAS_SETPGRP if setpgrp() is
+	available to set the current process group.
+
+d_setpgrp2 (d_setpgrp2.U):
+	This variable conditionally defines the HAS_SETPGRP2 symbol, which
+	indicates to the C program that the setpgrp2() (as in DG/UX) routine
+	is available to set the current process group.
+
+d_setprior (d_setprior.U):
+	This variable conditionally defines HAS_SETPRIORITY if setpriority()
+	is available to set a process's priority.
+
+d_setregid (d_setregid.U):
+	This variable conditionally defines HAS_SETREGID if setregid() is
+	available to change the real and effective gid of the current
+	process.
+
+d_setresgid (d_setregid.U):
+	This variable conditionally defines HAS_SETRESGID if setresgid() is
+	available to change the real, effective and saved gid of the current
+	process.
+
+d_setresuid (d_setreuid.U):
+	This variable conditionally defines HAS_SETREUID if setresuid() is
+	available to change the real, effective and saved uid of the current
+	process.
+
+d_setreuid (d_setreuid.U):
+	This variable conditionally defines HAS_SETREUID if setreuid() is
+	available to change the real and effective uid of the current
+	process.
+
+d_setrgid (d_setrgid.U):
+	This variable conditionally defines the HAS_SETRGID symbol, which
+	indicates to the C program that the setrgid() routine is available
+	to change the real gid of the current program.
+
+d_setruid (d_setruid.U):
+	This variable conditionally defines the HAS_SETRUID symbol, which
+	indicates to the C program that the setruid() routine is available
+	to change the real uid of the current program.
+
+d_setsid (d_setsid.U):
+	This variable conditionally defines HAS_SETSID if setsid() is
+	available to set the process group ID.
+
+d_sfio (d_sfio.U):
+	This variable conditionally defines the USE_SFIO symbol,
+	and indicates whether sfio is available (and should be used).
+
+d_shm (d_shm.U):
+	This variable conditionally defines the HAS_SHM symbol, which
+	indicates that the entire shm*(2) library is present.
+
+d_shmatprototype (d_shmat.U):
+	This variable conditionally defines the HAS_SHMAT_PROTOTYPE 
+	symbol, which indicates that sys/shm.h has a prototype for
+	shmat.
+
+d_sigaction (d_sigaction.U):
+	This variable conditionally defines the HAS_SIGACTION symbol, which
+	indicates that the Vr4 sigaction() routine is available.
+
+d_sigsetjmp (d_sigsetjmp.U):
+	This variable conditionally defines the HAS_SIGSETJMP symbol,
+	which indicates that the sigsetjmp() routine is available to
+	call setjmp() and optionally save the process's signal mask.
+
+d_socket (d_socket.U):
+	This variable conditionally defines HAS_SOCKET, which indicates
+	that the BSD socket interface is supported.
+
+d_sockpair (d_socket.U):
+	This variable conditionally defines the HAS_SOCKETPAIR symbol, which
+	indicates that the BSD socketpair() is supported.
+
+d_statblks (d_statblks.U):
+	This variable conditionally defines USE_STAT_BLOCKS if this system
+	has a stat structure declaring st_blksize and st_blocks.
+
+d_stdio_cnt_lval (d_stdstdio.U):
+	This variable conditionally defines STDIO_CNT_LVALUE if the
+	FILE_cnt macro can be used as an lvalue.
+
+d_stdio_ptr_lval (d_stdstdio.U):
+	This variable conditionally defines STDIO_PTR_LVALUE if the
+	FILE_ptr macro can be used as an lvalue.
+
+d_stdiobase (d_stdstdio.U):
+	This variable conditionally defines USE_STDIO_BASE if this system
+	has a FILE structure declaring a usable _base field (or equivalent)
+	in stdio.h.
+
+d_stdstdio (d_stdstdio.U):
+	This variable conditionally defines USE_STDIO_PTR if this system
+	has a FILE structure declaring usable _ptr and _cnt fields (or
+	equivalent) in stdio.h.
+
+d_strchr (d_strchr.U):
+	This variable conditionally defines HAS_STRCHR if strchr() and
+	strrchr() are available for string searching.
+
+d_strcoll (d_strcoll.U):
+	This variable conditionally defines HAS_STRCOLL if strcoll() is
+	available to compare strings using collating information.
+
+d_strctcpy (d_strctcpy.U):
+	This variable conditionally defines the USE_STRUCT_COPY symbol, which
+	indicates to the C program that this C compiler knows how to copy
+	structures.
+
+d_strerrm (d_strerror.U):
+	This variable holds what Strerrr is defined as to translate an error
+	code condition into an error message string. It could be 'strerror'
+	or a more complex macro emulating strrror with sys_errlist[], or the
+	"unknown" string when both strerror and sys_errlist are missing.
+
+d_strerror (d_strerror.U):
+	This variable conditionally defines HAS_STRERROR if strerror() is
+	available to translate error numbers to strings.
+
+d_strxfrm (d_strxfrm.U):
+	This variable conditionally defines HAS_STRXFRM if strxfrm() is
+	available to transform strings.
+
+d_suidsafe (d_dosuid.U):
+	This variable conditionally defines SETUID_SCRIPTS_ARE_SECURE_NOW
+	if setuid scripts can be secure.  This test looks in /dev/fd/.
+
+d_symlink (d_symlink.U):
+	This variable conditionally defines the HAS_SYMLINK symbol, which
+	indicates to the C program that the symlink() routine is available
+	to create symbolic links.
+
+d_syscall (d_syscall.U):
+	This variable conditionally defines HAS_SYSCALL if syscall() is
+	available call arbitrary system calls.
+
+d_sysconf (d_sysconf.U):
+	This variable conditionally defines the HAS_SYSCONF symbol, which
+	indicates to the C program that the sysconf() routine is available
+	to determine system related limits and options.
+
+d_syserrlst (d_strerror.U):
+	This variable conditionally defines HAS_SYS_ERRLIST if sys_errlist[] is
+	available to translate error numbers to strings.
+
+d_system (d_system.U):
+	This variable conditionally defines HAS_SYSTEM if system() is
+	available to issue a shell command.
+
+d_tcgetpgrp (d_tcgtpgrp.U):
+	This variable conditionally defines the HAS_TCGETPGRP symbol, which
+	indicates to the C program that the tcgetpgrp() routine is available.
+	to get foreground process group ID.
+
+d_tcsetpgrp (d_tcstpgrp.U):
+	This variable conditionally defines the HAS_TCSETPGRP symbol, which
+	indicates to the C program that the tcsetpgrp() routine is available
+	to set foreground process group ID.
+
+d_telldir (d_readdir.U):
+	This variable conditionally defines HAS_TELLDIR if telldir() is
+	available.
+
+d_times (d_times.U):
+	This variable conditionally defines the HAS_TIMES symbol, which indicates
+	that the times() routine exists.  The times() routine is normaly
+	provided on UNIX systems. You may have to include <sys/times.h>.
+
+d_truncate (d_truncate.U):
+	This variable conditionally defines HAS_TRUNCATE if truncate() is
+	available to truncate files.
+
+d_tzname (d_tzname.U):
+	This variable conditionally defines HAS_TZNAME if tzname[] is
+	available to access timezone names.
+
+d_umask (d_umask.U):
+	This variable conditionally defines the HAS_UMASK symbol, which
+	indicates to the C program that the umask() routine is available.
+	to set and get the value of the file creation mask.
+
+d_uname (d_gethname.U):
+	This variable conditionally defines the HAS_UNAME symbol, which
+	indicates to the C program that the uname() routine may be
+	used to derive the host name.
+
+d_vfork (d_vfork.U):
+	This variable conditionally defines the HAS_VFORK symbol, which
+	indicates the vfork() routine is available.
+
+d_void_closedir (d_closedir.U):
+	This variable conditionally defines VOID_CLOSEDIR if closedir()
+	does not return a value.
+
+d_volatile (d_volatile.U):
+	This variable conditionally defines the HASVOLATILE symbol, which
+	indicates to the C program that this C compiler knows about the
+	volatile declaration.
+
+d_vprintf (d_vprintf.U):
+	This variable conditionally defines the HAS_VPRINTF symbol, which
+	indicates to the C program that the vprintf() routine is available
+	to printf with a pointer to an argument list.
+
+d_wait4 (d_wait4.U):
+	This variable conditionally defines the HAS_WAIT4 symbol, which
+	indicates the wait4() routine is available.
+
+d_waitpid (d_waitpid.U):
+	This variable conditionally defines HAS_WAITPID if waitpid() is
+	available to wait for child process.
+
+d_wcstombs (d_wcstombs.U):
+	This variable conditionally defines the HAS_WCSTOMBS symbol, which
+	indicates to the C program that the wcstombs() routine is available
+	to convert wide character strings to multibyte strings.
+
+d_wctomb (d_wctomb.U):
+	This variable conditionally defines the HAS_WCTOMB symbol, which
+	indicates to the C program that the wctomb() routine is available
+	to convert a wide character to a multibyte.
+
+db_hashtype (i_db.U):
+	This variable contains the type of the hash structure element
+	in the <db.h> header file.  In older versions of DB, it was
+	int, while in newer ones it is u_int32_t.
+
+db_prefixtype (i_db.U):
+	This variable contains the type of the prefix structure element
+	in the <db.h> header file.  In older versions of DB, it was
+	int, while in newer ones it is size_t.
+
+direntrytype (i_dirent.U):
+	This symbol is set to 'struct direct' or 'struct dirent' depending on
+	whether dirent is available or not. You should use this pseudo type to
+	portably declare your directory entries.
+
+dlext (dlext.U):
+	This variable contains the extension that is to be used for the
+	dynamically loaded modules that perl generaties.
+
+dlsrc (dlsrc.U):
+	This variable contains the name of the dynamic loading file that
+	will be used with the package.
+
+dynamic_ext (Extensions.U):
+	This variable holds a list of extension files we want to
+	link dynamically into the package.  It is used by Makefile.
+
+eagain (nblock_io.U):
+	This variable bears the symbolic errno code set by read() when no
+	data is present on the file and non-blocking I/O was enabled (otherwise,
+	read() blocks naturally).
+
+eunicefix (Init.U):
+	When running under Eunice this variable contains a command which will
+	convert a shell script to the proper form of text file for it to be
+	executable by the shell.  On other systems it is a no-op.
+
+exe_ext (Unix.U):
+	This variable defines the extension used for executable files.
+	For unix it is empty.  Other possible values include '.exe'.
+
+firstmakefile (Unix.U):
+	This variable defines the first file searched by make.  On unix,
+	it is makefile (then Makefile).  On case-insensitive systems,
+	it might be something else.  This is only used to deal with
+	convoluted make depend tricks.
+
+fpostype (fpostype.U):
+	This variable defines Fpos_t to be something like fpost_t, long, 
+	uint, or whatever type is used to declare file positions in libc.
+
+freetype (mallocsrc.U):
+	This variable contains the return type of free().  It is usually
+	void, but occasionally int.
+
+full_csh (d_csh.U):
+	This variable contains the full pathname to 'csh', whether or
+	not the user has specified 'portability'.  This is only used
+	in the compiled C program, and we assume that all systems which
+	can share this executable will have the same full pathname to
+	'csh.'
+
+full_sed (Loc_sed.U):
+	This variable contains the full pathname to 'sed', whether or
+	not the user has specified 'portability'.  This is only used
+	in the compiled C program, and we assume that all systems which
+	can share this executable will have the same full pathname to
+	'sed.'
+
+gidtype (gidtype.U):
+	This variable defines Gid_t to be something like gid_t, int,
+	ushort, or whatever type is used to declare the return type
+	of getgid().  Typically, it is the type of group ids in the kernel.
+
+groupstype (groupstype.U):
+	This variable defines Groups_t to be something like gid_t, int, 
+	ushort, or whatever type is used for the second argument to
+	getgroups().  Usually, this is the same of gidtype, but
+	sometimes it isn't.
+
+i_dirent (i_dirent.U):
+	This variable conditionally defines I_DIRENT, which indicates
+	to the C program that it should include <dirent.h>.
+
+i_dlfcn (i_dlfcn.U):
+	This variable conditionally defines the I_DLFCN symbol, which
+	indicates to the C program that <dlfcn.h> exists and should
+	be included.
+
+i_fcntl (i_fcntl.U):
+	This variable controls the value of I_FCNTL (which tells
+	the C program to include <fcntl.h>).
+
+i_float (i_float.U):
+	This variable conditionally defines the I_FLOAT symbol, and indicates
+	whether a C program may include <float.h> to get symbols like DBL_MAX
+	or DBL_MIN, i.e. machine dependent floating point values.
+
+i_grp (i_grp.U):
+	This variable conditionally defines the I_GRP symbol, and indicates
+	whether a C program should include <grp.h>.
+
+i_limits (i_limits.U):
+	This variable conditionally defines the I_LIMITS symbol, and indicates
+	whether a C program may include <limits.h> to get symbols like WORD_BIT
+	and friends.
+
+i_locale (i_locale.U):
+	This variable conditionally defines the I_LOCALE symbol,
+	and indicates whether a C program should include <locale.h>.
+
+i_math (i_math.U):
+	This variable conditionally defines the I_MATH symbol, and indicates
+	whether a C program may include <math.h>.
+
+i_memory (i_memory.U):
+	This variable conditionally defines the I_MEMORY symbol, and indicates
+	whether a C program should include <memory.h>.
+
+i_neterrno (i_neterrno.U):
+	This variable conditionally defines the I_NET_ERRNO symbol, which
+	indicates to the C program that <net/errno.h> exists and should
+	be included.
+
+i_niin (i_niin.U):
+	This variable conditionally defines I_NETINET_IN, which indicates
+	to the C program that it should include <netinet/in.h>. Otherwise,
+	you may try <sys/in.h>.
+
+i_pwd (i_pwd.U):
+	This variable conditionally defines I_PWD, which indicates
+	to the C program that it should include <pwd.h>.
+
+i_rpcsvcdbm (i_dbm.U):
+	This variable conditionally defines the I_RPCSVC_DBM symbol, which
+	indicates to the C program that <rpcsvc/dbm.h> exists and should
+	be included.  Some System V systems might need this instead of <dbm.h>.
+
+i_sfio (i_sfio.U):
+	This variable conditionally defines the I_SFIO symbol,
+	and indicates whether a C program should include <sfio.h>.
+
+i_sgtty (i_termio.U):
+	This variable conditionally defines the I_SGTTY symbol, which
+	indicates to the C program that it should include <sgtty.h> rather
+	than <termio.h>.
+
+i_stdarg (i_varhdr.U):
+	This variable conditionally defines the I_STDARG symbol, which
+	indicates to the C program that <stdarg.h> exists and should
+	be included.
+
+i_stddef (i_stddef.U):
+	This variable conditionally defines the I_STDDEF symbol, which
+	indicates to the C program that <stddef.h> exists and should
+	be included.
+
+i_stdlib (i_stdlib.U):
+	This variable conditionally defines the I_STDLIB symbol, which
+	indicates to the C program that <stdlib.h> exists and should
+	be included.
+
+i_string (i_string.U):
+	This variable conditionally defines the I_STRING symbol, which
+	indicates that <string.h> should be included rather than <strings.h>.
+
+i_sysdir (i_sysdir.U):
+	This variable conditionally defines the I_SYS_DIR symbol, and indicates
+	whether a C program should include <sys/dir.h>.
+
+i_sysfile (i_sysfile.U):
+	This variable conditionally defines the I_SYS_FILE symbol, and indicates
+	whether a C program should include <sys/file.h> to get R_OK and friends.
+
+i_sysioctl (i_sysioctl.U):
+	This variable conditionally defines the I_SYS_IOCTL symbol, which
+	indicates to the C program that <sys/ioctl.h> exists and should
+	be included.
+
+i_sysndir (i_sysndir.U):
+	This variable conditionally defines the I_SYS_NDIR symbol, and indicates
+	whether a C program should include <sys/ndir.h>.
+
+i_sysparam (i_sysparam.U):
+	This variable conditionally defines the I_SYS_PARAM symbol, and indicates
+	whether a C program should include <sys/param.h>.
+
+i_sysresrc (i_sysresrc.U):
+	This variable conditionally defines the I_SYS_RESOURCE symbol,
+	and indicates whether a C program should include <sys/resource.h>.
+
+i_sysselct (i_sysselct.U):
+	This variable conditionally defines I_SYS_SELECT, which indicates
+	to the C program that it should include <sys/select.h> in order to
+	get the definition of struct timeval.
+
+i_sysstat (i_sysstat.U):
+	This variable conditionally defines the I_SYS_STAT symbol,
+	and indicates whether a C program should include <sys/stat.h>.
+
+i_systime (i_time.U):
+	This variable conditionally defines I_SYS_TIME, which indicates
+	to the C program that it should include <sys/time.h>.
+
+i_systimek (i_time.U):
+	This variable conditionally defines I_SYS_TIME_KERNEL, which
+	indicates to the C program that it should include <sys/time.h>
+	with KERNEL defined.
+
+i_systimes (i_systimes.U):
+	This variable conditionally defines the I_SYS_TIMES symbol, and indicates
+	whether a C program should include <sys/times.h>.
+
+i_systypes (i_systypes.U):
+	This variable conditionally defines the I_SYS_TYPES symbol,
+	and indicates whether a C program should include <sys/types.h>.
+
+i_sysun (i_sysun.U):
+	This variable conditionally defines I_SYS_UN, which indicates
+	to the C program that it should include <sys/un.h> to get UNIX
+	domain socket definitions.
+
+i_syswait (i_syswait.U):
+	This variable conditionally defines I_SYS_WAIT, which indicates
+	to the C program that it should include <sys/wait.h>.
+
+i_termio (i_termio.U):
+	This variable conditionally defines the I_TERMIO symbol, which
+	indicates to the C program that it should include <termio.h> rather
+	than <sgtty.h>.
+
+i_termios (i_termio.U):
+	This variable conditionally defines the I_TERMIOS symbol, which
+	indicates to the C program that the POSIX <termios.h> file is
+	to be included.
+
+i_time (i_time.U):
+	This variable conditionally defines I_TIME, which indicates
+	to the C program that it should include <time.h>.
+
+i_unistd (i_unistd.U):
+	This variable conditionally defines the I_UNISTD symbol, and indicates
+	whether a C program should include <unistd.h>.
+
+i_utime (i_utime.U):
+	This variable conditionally defines the I_UTIME symbol, and indicates
+	whether a C program should include <utime.h>.
+
+i_values (i_values.U):
+	This variable conditionally defines the I_VALUES symbol, and indicates
+	whether a C program may include <values.h> to get symbols like MAXLONG
+	and friends.
+
+i_varargs (i_varhdr.U):
+	This variable conditionally defines I_VARARGS, which indicates
+	to the C program that it should include <varargs.h>.
+
+i_varhdr (i_varhdr.U):
+	Contains the name of the header to be included to get va_dcl definition.
+	Typically one of varargs.h or stdarg.h.
+
+i_vfork (i_vfork.U):
+	This variable conditionally defines the I_VFORK symbol, and indicates
+	whether a C program should include vfork.h.
+
+installbin (bin.U):
+	This variable is the same as binexp unless AFS is running in which case
+	the user is explicitely prompted for it. This variable should always
+	be used in your makefiles for maximum portability.
+
+installprivlib (privlib.U):
+	This variable is really the same as privlibexp but may differ on
+	those systems using AFS. For extra portability, only this variable
+	should be used in makefiles.
+
+intsize (intsize.U):
+	This variable contains the value of the INTSIZE symbol,
+	which indicates to the C program how many bytes there are
+	in an integer.
+
+large (models.U):
+	This variable contains a flag which will tell the C compiler and loader
+	to produce a program running with a large memory model.  It is up to
+	the Makefile to use this.
+
+ld (dlsrc.U):
+	This variable indicates the program to be used to link
+	libraries for dynamic loading.  On some systems, it is 'ld'.
+	On ELF systems, it should be $cc.  Mostly, we'll try to respect
+	the hint file setting.
+
+lddlflags (dlsrc.U):
+	This variable contains any special flags that might need to be
+	passed to $ld to create a shared library suitable for dynamic
+	loading.  It is up to the makefile to use it.  For hpux, it
+	should be -b.  For sunos 4.1, it is empty.
+
+ldflags (ccflags.U):
+	This variable contains any additional C loader flags desired by
+	the user.  It is up to the Makefile to use this.
+
+lib_ext (Unix.U):
+	This variable defines the extension used for ordinary libraries.
+	For unix, it is '.a'.  The '.' is included.  Other possible
+	values include '.lib'.
+
+libperl (libperl.U):
+	The perl executable is obtained by linking perlmain.c with
+	libperl, any static extensions (usually just DynaLoader),
+	and any other libraries needed on this system.  libperl
+	is usually libperl.a, but can also be libperl.so.xxx if
+	the user wishes to build a perl executable with a shared
+	library.
+
+libs (libs.U):
+	This variable holds the additional libraries we want to use.
+	It is up to the Makefile to deal with it.
+
+lns (lns.U):
+	This variable holds the name of the command to make 
+	symbolic links (if they are supported).  It can be used
+	in the Makefile. It is either 'ln -s' or 'ln'
+
+lseektype (lseektype.U):
+	This variable defines lseektype to be something like off_t, long, 
+	or whatever type is used to declare lseek offset's type in the
+	kernel (which also appears to be lseek's return type).
+
+make (make.U):
+	This variable sets the path to the 'make' command.  It is
+	here rather than in Loc.U so that users can override it
+	with  Configure -Dmake=pmake, or equivalent.
+
+make_set_make (make.U):
+	Some versions of 'make' set the variable MAKE.  Others do not.
+	This variable contains the string to be included in Makefile.SH
+	so that MAKE is set if needed, and not if not needed.
+	Possible values are:
+	make_set_make='#'	# If your make program handles this for you,
+	make_set_make=$make	# if it doesn't.
+	I used a comment character so that we can distinguish a
+	'set' value (from a previous config.sh or Configure -D option)
+	from an uncomputed value.
+
+mallocobj (mallocsrc.U):
+	This variable contains the name of the malloc.o that this package
+	generates, if that malloc.o is preferred over the system malloc.
+	Otherwise the value is null.  This variable is intended for generating
+	Makefiles.  See mallocsrc.
+
+mallocsrc (mallocsrc.U):
+	This variable contains the name of the malloc.c that comes with
+	the package, if that malloc.c is preferred over the system malloc.
+	Otherwise the value is null.  This variable is intended for generating
+	Makefiles.
+
+malloctype (mallocsrc.U):
+	This variable contains the kind of ptr returned by malloc and realloc.
+
+man1dir (man1dir.U):
+	This variable contains the name of the directory in which manual
+	source pages are to be put.  It is the responsibility of the
+	Makefile.SH to get the value of this into the proper command.
+	You must be prepared to do the ~name expansion yourself.
+
+man1ext (man1dir.U):
+	This variable contains the extension that the manual page should
+	have: one of 'n', 'l', or '1'.  The Makefile must supply the '.'.
+	See man1dir.
+
+man3dir (man3dir.U):
+	This variable contains the name of the directory in which manual
+	source pages are to be put.  It is the responsibility of the
+	Makefile.SH to get the value of this into the proper command.
+	You must be prepared to do the ~name expansion yourself.
+
+man3ext (man3dir.U):
+	This variable contains the extension that the manual page should
+	have: one of 'n', 'l', or '3'.  The Makefile must supply the '.'.
+	See man3dir.
+
+modetype (modetype.U):
+	This variable defines modetype to be something like mode_t, 
+	int, unsigned short, or whatever type is used to declare file 
+	modes for system calls.
+
+n (n.U):
+	This variable contains the -n flag if that is what causes the echo
+	command to suppress newline.  Otherwise it is null.  Correct usage is
+	    $echo $n "prompt for a question: $c".
+
+o_nonblock (nblock_io.U):
+	This variable bears the symbol value to be used during open() or fcntl()
+	to turn on non-blocking I/O for a file descriptor. If you wish to switch
+	between blocking and non-blocking, you may try ioctl(FIOSNBIO) instead,
+	but that is only supported by some devices.
+
+oldarchlib (oldarchlib.U):
+	This variable holds the name of the directory in which perl5.000
+	and perl5.001 stored 
+	architecture-dependent public library files.
+
+oldarchlibexp (oldarchlib.U):
+	This variable is the same as the oldarchlib variable, but is 
+	filename expanded at configuration time, for convenient use.
+
+optimize (ccflags.U):
+	This variable contains any optimizer/debugger flag that should be used.
+	It is up to the Makefile to use it.
+
+osname (Oldconfig.U):
+	This variable contains the operating system name (e.g. sunos,
+	solaris, hpux, etc.).  It can be useful later on for setting
+	defaults.  Any spaces are replaced with underscores.  It is set
+	to a null string if we can't figure it out.
+
+pager (pager.U):
+	This variable contains the name of the preferred pager on the system.
+	Usual values are (the full pathnames of) more, less, pg, or cat.
+
+path_sep (Unix.U):
+	This variable defines the character used to separate elements in
+	the shell's PATH environment variable.  On Unix, it is ':'.
+	This is probably identical to Head.U's p_ variable and can
+	probably be dropped.
+
+perladmin (perladmin.U):
+	Electronic mail address of the perl5 administrator.
+
+prefix (prefix.U):
+	This variable holds the name of the directory below which the
+	user will install the package.  Usually, this is /usr/local, and
+	executables go in /usr/local/bin, library stuff in /usr/local/lib,
+	man pages in /usr/local/man, etc.  It is only used to set defaults
+	for things in bin.U, mansrc.U, privlib.U, or scriptdir.U.
+
+privlib (privlib.U):
+	This variable contains the eventual value of the PRIVLIB symbol,
+	which is the name of the private library for this package.  It may
+	have a ~ on the front. It is up to the makefile to eventually create
+	this directory while performing installation (with ~ substitution).
+
+privlibexp (privlib.U):
+	This variable is the ~name expanded version of privlib, so that you
+	may use it directly in Makefiles or shell scripts.
+
+prototype (prototype.U):
+	This variable holds the eventual value of CAN_PROTOTYPE, which
+	indicates the C compiler can handle funciton prototypes.
+
+randbits (randbits.U):
+	This variable contains the eventual value of the RANDBITS symbol,
+	which indicates to the C program how many bits of random number
+	the rand() function produces.
+
+ranlib (orderlib.U):
+	This variable is set to the pathname of the ranlib program, if it is
+	needed to generate random libraries.  Set to ":" if ar can generate
+	random libraries or if random libraries are not supported
+
+rd_nodata (nblock_io.U):
+	This variable holds the return code from read() when no data is
+	present. It should be -1, but some systems return 0 when O_NDELAY is
+	used, which is a shame because you cannot make the difference between
+	no data and an EOF.. Sigh!
+
+scriptdir (scriptdir.U):
+	This variable holds the name of the directory in which the user wants
+	to put publicly scripts for the package in question.  It is either
+	the same directory as for binaries, or a special one that can be
+	mounted across different architectures, like /usr/share. Programs
+	must be prepared to deal with ~name expansion.
+
+selecttype (selecttype.U):
+	This variable holds the type used for the 2nd, 3rd, and 4th
+	arguments to select.  Usually, this is 'fd_set *', if HAS_FD_SET
+	is defined, and 'int *' otherwise.  This is only useful if you 
+	have select(), naturally.
+
+sh (sh.U):
+	This variable contains the full pathname of the shell used
+	on this system to execute Bourne shell scripts.  Usually, this will be
+	/bin/sh, though it's possible that some systems will have /bin/ksh,
+	/bin/pdksh, /bin/ash, /bin/bash, or even something such as D:/bin/sh.
+	This unit comes before Options.U, so you can't set sh with a -D
+	option, though you can override this (and startsh)
+	with -O -Dsh=/bin/whatever -Dstartsh=whatever
+
+shmattype (d_shmat.U):
+	This symbol contains the type of pointer returned by shmat().
+	It can be 'void *' or 'char *'.
+
+sig_name (sig_name.U):
+	This variable holds the signal names, space separated. The leading
+	SIG in signals name is removed. See sig_num.
+
+sig_num (sig_name.U):
+	This variable holds the signal numbers, space separated. Those numbers
+	correspond to the value of the signal listed in the same place within
+	the sig_name list.
+
+signal_t (d_voidsig.U):
+	This variable holds the type of the signal handler (void or int).
+
+sitearch (sitearch.U):
+	This variable contains the eventual value of the SITEARCH symbol,
+	which is the name of the private library for this package.  It may
+	have a ~ on the front. It is up to the makefile to eventually create
+	this directory while performing installation (with ~ substitution).
+
+sitearchexp (sitearch.U):
+	This variable is the ~name expanded version of sitearch, so that you
+	may use it directly in Makefiles or shell scripts.
+
+sitelib (sitelib.U):
+	This variable contains the eventual value of the SITELIB symbol,
+	which is the name of the private library for this package.  It may
+	have a ~ on the front. It is up to the makefile to eventually create
+	this directory while performing installation (with ~ substitution).
+
+sitelibexp (sitelib.U):
+	This variable is the ~name expanded version of sitelib, so that you
+	may use it directly in Makefiles or shell scripts.
+
+sizetype (sizetype.U):
+	This variable defines sizetype to be something like size_t, 
+	unsigned long, or whatever type is used to declare length 
+	parameters for string functions.
+
+small (models.U):
+	This variable contains a flag which will tell the C compiler and loader
+	to produce a program running with a small memory model.  It is up to
+	the Makefile to use this.
+
+spitshell (spitshell.U):
+	This variable contains the command necessary to spit out a runnable
+	shell on this system.  It is either cat or a grep -v for # comments.
+
+split (models.U):
+	This variable contains a flag which will tell the C compiler and loader
+	to produce a program that will run in separate I and D space, for those
+	machines that support separation of instruction and data space.  It is
+	up to the Makefile to use this.
+
+ssizetype (ssizetype.U):
+	This variable defines ssizetype to be something like ssize_t, 
+	long or int.  It is used by functions that return a count 
+	of bytes or an error condition.  It must be a signed type.
+	We will pick a type such that sizeof(SSize_t) == sizeof(Size_t).
+
+startperl (startperl.U):
+	This variable contains the string to put on the front of a perl
+	script to make sure (hopefully) that it runs with perl and not some
+	shell. Of course, that leading line must be followed by the classical
+	perl idiom:
+		eval 'exec perl -S $0 "$@"'
+			if $running_under_some_shell;
+	to guarantee perl startup should the shell execute the script. Note
+	that this magic incatation is not understood by csh.
+
+startsh (startsh.U):
+	This variable contains the string to put on the front of a shell
+	script to make sure (hopefully) that it runs with sh and not some
+	other shell.
+
+static_ext (Extensions.U):
+	This variable holds a list of extension files we want to
+	link statically into the package.  It is used by Makefile.
+
+stdchar (stdchar.U):
+	This variable conditionally defines STDCHAR to be the type of char
+	used in stdio.h.  It has the values "unsigned char" or "char".
+
+timetype (d_time.U):
+	This variable holds the type returned by time(). It can be long,
+	or time_t on BSD sites (in which case <sys/types.h> should be
+	included). Anyway, the type Time_t should be used.
+
+uidtype (uidtype.U):
+	This variable defines Uid_t to be something like uid_t, int, 
+	ushort, or whatever type is used to declare user ids in the kernel.
+
+useperlio (useperlio.U):
+	This variable conditionally defines the USE_PERLIO symbol,
+	and indicates that the PerlIO abstraction should be
+	used throughout.
+
+useshrplib (libperl.U):
+	This variable is set to 'yes' if the user wishes
+	to build a shared libperl, and 'no' otherwise.
+
+voidflags (voidflags.U):
+	This variable contains the eventual value of the VOIDFLAGS symbol,
+	which indicates how much support of the void type is given by this
+	compiler.  See VOIDFLAGS for more info.
+