Removed CFront 1.2 -specific code from skeleton, because CFront now defines __cplusplus properly.

Removed TurboC-specific code from skeleton.
Skeleton now includes proper C++ standard headers.
Relocated "unistd.h" code after user section 1 to allow user to overrid it.
New option "nounistd" to suppress unistd.h from being included.

6 files changed, 42 insertions, 37 deletions

diff --git a/flex.skl b/flex.skl
index 25342d4..0ba0880 100644
--- a/flex.skl
+++ b/flex.skl
@@ -23,29 +23,24 @@
 #define YY_FLEX_MINOR_VERSION 5
 
 %-
+/* begin standard C headers. */
 #include <stdio.h>
 #include <errno.h>
+#include <stdlib.h>
+/* end standard C headers. */
 %+
+/* begin standard C++ headers. */
+#include <iostream> 
 #include <cerrno>
+#include <cstdlib>
+/* end standard C++ headers. */
 %*
 
-
-/* cfront 1.2 defines "c_plusplus" instead of "__cplusplus" */
-#ifdef c_plusplus
-#ifndef __cplusplus
-#define __cplusplus
-#endif
-#endif
-
-
 #ifdef __cplusplus
 
-#include <stdlib.h>
 %+
 #define FLEX_STD   std::
-#include <iostream>
 %*
-#include <unistd.h>
 
 /* Use prototypes in function declarations. */
 #define YY_USE_PROTOS
@@ -63,15 +58,6 @@
 #endif	/* __STDC__ */
 #endif	/* ! __cplusplus */
 
-#ifdef __TURBOC__
- #pragma warn -rch
- #pragma warn -use
-#include <io.h>
-#include <stdlib.h>
-#define YY_USE_CONST
-#define YY_USE_PROTOS
-#endif
-
 #ifdef YY_USE_CONST
 #define yyconst const
 #else
@@ -402,6 +388,19 @@ static void yy_fatal_error YY_PROTO(( yyconst char msg[] ));
 %% [4.0] data tables for the DFA and the user's section 1 definitions go here
 %e
 
+/* Special case for "unistd.h", since it is non-ANSI. We include it way
+ * down here because we want the user's section 1 to have been scanned first.
+ * The user has a chance to override it with an option.
+ */
+#ifndef YY_NO_UNISTD_H
+%-
+#include <unistd.h>
+%+
+#include <cunistd>
+%*
+#endif /* !YY_NO_UNISTD_H */
+
+
 #ifndef YY_EXTRA_TYPE
 #define YY_EXTRA_TYPE void *
 #endif
@@ -591,21 +590,6 @@ static int yy_top_state YY_PROTO(( YY_ONLY_ARG ));
 #define YY_NO_TOP_STATE 1
 #endif
 
-#ifdef YY_MALLOC_DECL
-YY_MALLOC_DECL
-#else
-#if __STDC__
-#ifndef __cplusplus
-#include <stdlib.h>
-#endif
-#else
-/* Just try to get by without declaring the routines.  This will fail
- * miserably on non-ANSI systems for which sizeof(size_t) != sizeof(int)
- * or sizeof(void*) != sizeof(int).
- */
-#endif
-#endif
-
 /* Amount of stuff to slurp up with each read. */
 #ifndef YY_READ_BUF_SIZE
 #define YY_READ_BUF_SIZE 8192
diff --git a/flex.texi b/flex.texi
index b3a0231..8f61aac 100644
--- a/flex.texi
+++ b/flex.texi
@@ -2276,6 +2276,7 @@ classes are often a big win when using compressed tables, but they
 have a moderate performance impact (one or two @code{if} tests and one
 array look-up per character scanned).
 
+@anchor{option-read}
 @item -Cr, --read
 causes the generated scanner to @emph{bypass} use of the standard I/O
 library (@code{stdio}) for input.  Instead of calling @code{fread()} or
@@ -2387,6 +2388,7 @@ constructs its scanners.  You'll never need this option unless you are doing
 @code{flex}
 maintenance or development.
 
+@anchor{option-always-interactive}
 @item --always-interactive
 instructs flex to generate a scanner which always considers its input
 @emph{interactive}.  Normally, on each new input file the scanner calls
@@ -2403,6 +2405,15 @@ scanner, which simply calls @code{yylex()}.  This option implies
 instructs flex to generate a scanner which never considers its input
 interactive.  This is the opposite of @code{always-interactive}.
 
+@item --nounistd
+suppresses inclusion of the non-ANSI header file @file{unistd.h}. This option
+is meant to target environments in which @file{unistd.h} does not exist. Be aware
+that certain options may cause flex to generate code that relies on functions
+normally found in @file{unistd.h}, (e.g. @code{isatty()}, @code{read()}.)
+If you wish to use these functions, you will have to inform your compiler where
+to find them.
+@xref{option-always-interactive}. @xref{option-read}.
+
 @item --stack
 enables the use of
 start condition stacks (@pxref{start conditions}).  
@@ -2471,6 +2482,7 @@ leading @samp{--} ).
     interactive     -I   --interactive
     lex-compat      -l   --lex-compat
     meta-ecs        -Cm  --meta-ecs
+    nounistd             --nounistd
     perf-report     -p   --perf-report
     pointer              --pointer equivalent to "%pointer" (default)
     prefix="PREFIX" -P   --prefix
diff --git a/main.c b/main.c
index 0ad0dc1..b679d4d 100644
--- a/main.c
+++ b/main.c
@@ -573,6 +573,7 @@ int exit_status;
             fprintf(header_out,"#undef YY_NO_SET_LVAL\n");
             fprintf(header_out,"#undef YY_NO_SET_OUT\n");
             fprintf(header_out,"#undef YY_NO_TOP_STATE\n");
+            fprintf(header_out,"#undef YY_NO_UNISTD_H\n");
             fprintf(header_out,"#undef YY_NO_UNPUT\n");
             fprintf(header_out,"#undef YY_NULL\n");
             fprintf(header_out,"#undef YY_NUM_RULES\n");
@@ -1100,7 +1101,11 @@ char **argv;
             case OPT_STDOUT:
                     use_stdout = true;
                     break;
-
+                    
+            case OPT_NO_UNISTD_H:
+                    buf_strdefine(&userdef_buf,"YY_NO_UNISTD_H", "1");
+                    break;
+                
             case OPT_TRACE:
                     trace = true;
                     break;
@@ -1718,6 +1723,7 @@ _(
 "  -R,  --reentrant         generate a reentrant C scanner\n"
 "  -Rb, --reentrant-bison   reentrant scanner for bison pure parser.\n"
 "       --stdinit           initialize yyin/yyout to stdin/stdout\n"
+"       --nounistd          do not include <unistd.h>\n"
 "       --noFUNCTION        do not generate a particular FUNCTION\n"
 
 "\n"
diff --git a/options.c b/options.c
index b84df15..45e64fd 100644
--- a/options.c
+++ b/options.c
@@ -79,6 +79,7 @@ optspec_t  flexopts[] = {
 {"--stdout",            OPT_STDOUT,0},/* Write generated scanner to stdout. */
 {"-T",                  OPT_TRACE,0},
 {"--trace",             OPT_TRACE,0},/* Flex should run in trace mode. */
+{"--nounistd",          OPT_NO_UNISTD_H,0}, /* Do not include unistd.h */
 {"-v",                  OPT_VERBOSE,0},
 {"--verbose",           OPT_VERBOSE,0},/* Write summary of scanner statistics to stdout. */
 {"-V",                  OPT_VERSION,0},
diff --git a/options.h b/options.h
index cb27e90..3326336 100644
--- a/options.h
+++ b/options.h
@@ -79,6 +79,7 @@ enum flexopt_flag_t {
     OPT_STDINIT,
     OPT_STDOUT,
     OPT_TRACE,
+    OPT_NO_UNISTD_H,
     OPT_VERBOSE,
     OPT_VERSION,
     OPT_WARN,
diff --git a/scan.l b/scan.l
index ec2bbbf..e86132f 100644
--- a/scan.l
+++ b/scan.l
@@ -269,6 +269,7 @@ LEXOPT		[aceknopr]
 	stack		action_define( "YY_STACK_USED", option_sense );
 	stdinit		do_stdinit = option_sense;
 	stdout		use_stdout = option_sense;
+    unistd      ACTION_IFDEF("YY_NO_UNISTD_H", ! option_sense);
 	unput		ACTION_IFDEF("YY_NO_UNPUT", ! option_sense);
 	verbose		printstats = option_sense;
 	warn		nowarn = ! option_sense;