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# Autoconf macros for xdvik.
# Copyright (C) 2002 - 2009 Paul Vojta <xdvi-core@lists.sourceforge.net>
#
# This file is free software; the copyright holder
# gives unlimited permission to copy and/or distribute it,
# with or without modifications, as long as this notice is preserved.
# XDVI_FUNC_SETSID_IN_VFORK
# -------------------------
# Check for whether setsid() is allowed within vfork()
# (Mac OS X 10.3 (Panther, 11/2003) is one O/S which does not allow this).
AC_DEFUN([XDVI_FUNC_SETSID_IN_VFORK],
[AS_IF([test "x$ac_cv_func_vfork_works" = xyes],
[AC_CACHE_CHECK([for whether setsid() is allowed within vfork()],
[xdvi_cv_setsid_in_vfork],
[AC_RUN_IFELSE([AC_LANG_PROGRAM([[
/* Test adapted from Gnu autoconf */
/* Thanks to Paul Eggert for this test. */
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef HAVE_VFORK_H
#include <vfork.h>
#endif]],
[[
pid_t parent = getpid ();
pid_t child;
child = vfork ();
if (child == 0) {
if (setsid () == -1)
_exit(1);
_exit(0);
} else {
int status;
while (wait(&status) != child)
;
exit(
/* Was there some problem with vforking? */
child < 0
/* Did the child fail? (This shouldn't happen.) */
|| status
);
}]])],
[xdvi_cv_setsid_in_vfork=yes],
[xdvi_cv_setsid_in_vfork=no],
[xdvi_cv_setsid_in_vfork=no # safe value for cross-compiling])])
if test "x$xdvi_cv_setsid_in_vfork" = xyes; then
AC_DEFINE([HAVE_GOOD_SETSID_VFORK], 1,
[Define if your system allows setsid() within vfork().])
fi])
]) # XDVI_FUNC_SETSID_IN_VFORK
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