-#serial 10
-dnl Copyright (C) 2002, 2005, 2007, 2009-2010 Free Software Foundation, Inc.
+#serial 12
+dnl Copyright (C) 2002, 2005, 2007, 2009-2011 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
dnl with or without modifications, as long as this notice is preserved.
[
AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
AC_REQUIRE([AC_CANONICAL_HOST])
- AC_CHECK_FUNCS_ONCE([dup2])
+ AC_CHECK_FUNCS_ONCE([dup2 fcntl])
if test $ac_cv_func_dup2 = no; then
HAVE_DUP2=0
AC_LIBOBJ([dup2])
AC_CACHE_CHECK([whether dup2 works], [gl_cv_func_dup2_works],
[AC_RUN_IFELSE([
AC_LANG_PROGRAM([[#include <unistd.h>
+#include <fcntl.h>
#include <errno.h>]],
- [if (dup2 (1, 1) == 0)
- return 1;
+ [int result = 0;
+#if HAVE_FCNTL
+ if (fcntl (1, F_SETFD, FD_CLOEXEC) == -1)
+ result |= 1;
+#endif HAVE_FCNTL
+ if (dup2 (1, 1) == 0)
+ result |= 2;
+#if HAVE_FCNTL
+ if (fcntl (1, F_GETFD) != FD_CLOEXEC)
+ result |= 4;
+#endif
close (0);
if (dup2 (0, 0) != -1)
- return 2;
+ result |= 8;
/* Many gnulib modules require POSIX conformance of EBADF. */
- if (dup2 (1, 1000000) == -1 && errno != EBADF)
- return 3;
- return 0;
+ if (dup2 (2, 1000000) == -1 && errno != EBADF)
+ result |= 16;
+ return result;
])
],
[gl_cv_func_dup2_works=yes], [gl_cv_func_dup2_works=no],
gl_cv_func_dup2_works=no;;
freebsd*) # on FreeBSD 6.1, dup2(1,1000000) gives EMFILE, not EBADF.
gl_cv_func_dup2_works=no;;
+ haiku*) # on Haiku alpha 2, dup2(1, 1) resets FD_CLOEXEC.
+ gl_cv_func_dup2_works=no;;
*) gl_cv_func_dup2_works=yes;;
esac])
])