3 dnl Copyright (C) 2009-2024 Free Software Foundation, Inc.
4 dnl This file is free software; the Free Software Foundation
5 dnl gives unlimited permission to copy and/or distribute it,
6 dnl with or without modifications, as long as this notice is preserved.
8 AC_DEFUN([gl_FUNC_DUP3],
10 AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
12 dnl Persuade glibc <unistd.h> to declare dup3().
13 AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])
15 AC_CHECK_FUNCS_ONCE([setdtablesize])
16 gl_CHECK_FUNCS_ANDROID([dup3], [[#include <unistd.h>]])
17 if test $ac_cv_func_dup3 != yes; then
19 case "$gl_cv_onwards_func_dup3" in
20 future*) REPLACE_DUP3=1 ;;
26 dnl Not needed yet, because dup3 is unconditionally replaced.
27 dnl dnl Replace dup3() for supporting the gnulib-defined fchdir() function,
28 dnl dnl to keep fchdir's bookkeeping up-to-date.
29 dnl m4_ifdef([gl_FUNC_FCHDIR], [
31 dnl if test $HAVE_FCHDIR = 0; then
32 dnl if test $HAVE_DUP3 = 1; then