Even better use64bitall logic.

[metaconfig.git] / U / perl / fflushall.U

?RCS: $Id$
?RCS:
?RCS: Copyright (c) 1999, Jarkko Hietaniemi
?RCS: 
?RCS: You may redistribute only under the terms of the Artistic Licence,
?RCS: as specified in the README file that comes with the distribution.
?RCS: You may reuse parts of this distribution only within the terms of
?RCS: that same Artistic Licence; a copy of which may be found at the root
?RCS: of the source tree for dist 3.0.
?RCS:
?MAKE:fflushNULL fflushall: Compile cat rm test osname \
	Oldconfig Myread Setvar exe_ext echo \
	d_sysconf i_unistd d_stdio_stream_array stdio_stream_array
?MAKE:	-pick add $@ %<
?S:fflushNULL:
?S:	This symbol, if defined, tells that fflush(NULL) does flush
?S:	all pending stdio output.
?S:.
?S:fflushall:
?S:	This symbol, if defined, tells that to flush
?S:	all pending stdio output one must loop through all
?S:	the stdio file handles stored in an array and fflush them.
?S:	Note that if fflushNULL is defined, fflushall will not
?S:	even be probed for and will be left undefined.
?S:.
?C:FFLUSH_NULL:
?C:	This symbol, if defined, tells that fflush(NULL) does flush
?C:	all pending stdio output.
?C:.
?C:FFLUSH_ALL:
?C:	This symbol, if defined, tells that to flush
?C:	all pending stdio output one must loop through all
?C:	the stdio file handles stored in an array and fflush them.
?C:	Note that if fflushNULL is defined, fflushall will not
?C:	even be probed for and will be left undefined.
?C:.
?H:#$fflushNULL	FFLUSH_NULL 		/**/
?H:#$fflushall	FFLUSH_ALL 		/**/
?H:.
?T:output code
?F:!try.out
echo " "
$cat >&4 <<EOM
Checking how to flush all pending stdio output...
EOM
# I only know how to find the first 32 possibly open files on SunOS.
# See also hints/sunos_4_1.sh and util.c  --AD
case "$osname" in
sunos) $echo '#define PERL_FFLUSH_ALL_FOPEN_MAX 32' > try.c ;;
esac
$cat >>try.c <<EOCP
#include <stdio.h>
#$i_unistd I_UNISTD
#ifdef I_UNISTD
# include <unistd.h>
#endif
#$d_sysconf HAS_SYSCONF
#$d_stdio_stream_array HAS_STDIO_STREAM_ARRAY
#ifdef HAS_STDIO_STREAM_ARRAY
# define STDIO_STREAM_ARRAY $stdio_stream_array
#endif
int main() {
  FILE* p = fopen("try.out", "w");
#ifdef TRY_FPUTC
  fputc('x', p);
#else
# ifdef TRY_FPRINTF
  fprintf(p, "x");
# endif
#endif
#ifdef TRY_FFLUSH_NULL
  fflush(NULL);
#endif
#ifdef TRY_FFLUSH_ALL
  {
    long open_max = -1;
# ifdef PERL_FFLUSH_ALL_FOPEN_MAX
    open_max = PERL_FFLUSH_ALL_FOPEN_MAX;
# else
#  if defined(HAS_SYSCONF) && defined(_SC_OPEN_MAX)
    open_max = sysconf(_SC_OPEN_MAX);
#  else
#   ifdef FOPEN_MAX
    open_max = FOPEN_MAX;
#   else
#    ifdef OPEN_MAX
    open_max = OPEN_MAX;
#    else
#     ifdef _NFILE
    open_max = _NFILE;
#     endif
#    endif
#   endif
#  endif
# endif 
# ifdef HAS_STDIO_STREAM_ARRAY
    if (open_max > 0) {
      long i;
      for (i = 0; i < open_max; i++)
	    if (STDIO_STREAM_ARRAY[i]._file >= 0 &&
		STDIO_STREAM_ARRAY[i]._file < open_max &&
		STDIO_STREAM_ARRAY[i]._flag)
		fflush(&STDIO_STREAM_ARRAY[i]);
    }	
  }
# endif
#endif
  _exit(42);
}
EOCP
: first we have to find out how _not_ to flush
if $test "X$fflushNULL" = X -o "X$fflushall" = X; then
    output=''
    set try -DTRY_FPUTC
    if eval $compile; then
	    $rm -f try.out
 	    ./try$exe_ext 2>/dev/null
	    if $test ! -s try.out -a "X$?" = X42; then
		output=-DTRY_FPUTC
	    fi
    fi
    case "$output" in
    '')
	    set try -DTRY_FPRINTF
	    $rm -f try.out
	    if eval $compile; then
		    $rm -f try.out
 		    ./try$exe_ext 2>/dev/null
		    if $test ! -s try.out -a "X$?" = X42; then
			output=-DTRY_FPRINTF
		    fi
	    fi
	;;
    esac
fi
: check for fflush NULL behaviour
case "$fflushNULL" in
'') 	set try -DTRY_FFLUSH_NULL $output
	if eval $compile; then
	        $rm -f try.out
	    	./try$exe_ext 2>/dev/null
		code="$?"
		if $test -s try.out -a "X$code" = X42; then
			fflushNULL="`$cat try.out`"
		else
			if $test "X$code" != X42; then
				$cat >&4 <<EOM
(If this test failed, don't worry, we'll try another method shortly.)
EOM
			fi
		fi
	fi
	$rm -f core try.core core.try.*
	case "$fflushNULL" in
	x)	$cat >&4 <<EOM
Your fflush(NULL) works okay.
EOM
		fflushNULL="$define"
		;;
	'')	$cat >&4 <<EOM
Your fflush(NULL) isn't working (contrary to ANSI C).
EOM
		fflushNULL="$undef"
		;;
	*)	$cat >&4 <<EOM
Cannot figure out whether your fflush(NULL) works or not.
I'm assuming it doesn't (contrary to ANSI C).
EOM
		fflushNULL="$undef"
		;;
	esac
	;;
$define|true|[yY]*)
	fflushNULL="$define"
	;;
*)
	fflushNULL="$undef"
	;;
esac
: check explicit looping only if NULL did not work
case "$fflushNULL" in
"$undef")
	: check for fflush all behaviour
	case "$fflushall" in
	'') 	set try -DTRY_FFLUSH_ALL $output
		if eval $compile; then
		        $cat >&4 <<EOM
(Now testing the other method--but note that also this may fail.)
EOM
			$rm -f try.out
		    	./try$exe_ext 2>/dev/null
			if $test -s try.out -a "X$?" = X42; then
				fflushall="`$cat try.out`"
			fi
		fi
		$rm -f core try.core core.try.*
		case "$fflushall" in
		x)	$cat >&4 <<EOM
Whew. Flushing explicitly all the stdio streams works.
EOM
			fflushall="$define"
			;;
		'')	$cat >&4 <<EOM
Sigh. Flushing explicitly all the stdio streams doesn't work.
EOM
			fflushall="$undef"
			;;
		*)	$cat >&4 <<EOM
Cannot figure out whether flushing stdio streams explicitly works or not.
I'm assuming it doesn't.
EOM
			fflushall="$undef"
			;;
		esac
		;;
	"$define"|true|[yY]*)
		fflushall="$define"
		;;
	*)
		fflushall="$undef"
		;;
	esac
	;;
*)	fflushall="$undef"	
	;;
esac
case "$fflushNULL$fflushall" in
undefundef)
	$cat <<EOM
I cannot figure out how to flush pending stdio output.
EOM
	;;
esac
$rm -f try.* try$exe_ext