diff options
Diffstat (limited to 'gnulib-m4/dup2.m4')
| -rw-r--r-- | gnulib-m4/dup2.m4 | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/gnulib-m4/dup2.m4 b/gnulib-m4/dup2.m4 new file mode 100644 index 00000000..2abc74cd --- /dev/null +++ b/gnulib-m4/dup2.m4 @@ -0,0 +1,35 @@ +#serial 6 +dnl Copyright (C) 2002, 2005, 2007, 2009 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_DEFUN([gl_FUNC_DUP2], +[ + AC_REQUIRE([gl_UNISTD_H_DEFAULTS]) + AC_REQUIRE([AC_CANONICAL_HOST]) + AC_CHECK_FUNCS_ONCE([dup2]) + if test $ac_cv_func_dup2 = no; then + HAVE_DUP2=0 + AC_LIBOBJ([dup2]) + else + AC_CACHE_CHECK([whether dup2 works], [gl_cv_func_dup2_works], + [AC_RUN_IFELSE([AC_LANG_PROGRAM([[ +#include <unistd.h> +]], [return 1 - dup2 (1, 1);])], + [gl_cv_func_dup2_works=yes], [gl_cv_func_dup2_works=no], + [case "$host_os" in + mingw*) # on this platform, dup2 always returns 0 for success + gl_cv_func_dup2_works=no;; + cygwin*) # on cygwin 1.5.x, dup2(1,1) returns 0 + gl_cv_func_dup2_works=no;; + *) gl_cv_func_dup2_works=yes;; + esac])]) + if test "$gl_cv_func_dup2_works" = no; then + REPLACE_DUP2=1 + AC_LIBOBJ([dup2]) + fi + fi + AC_DEFINE_UNQUOTED([REPLACE_DUP2], [$REPLACE_DUP2], + [Define to 1 if dup2 returns 0 instead of the target fd.]) +]) |