2 dnl Copyright (C) 2010-2018 Free Software Foundation, Inc.
3 dnl This file is free software; the Free Software Foundation
4 dnl gives unlimited permission to copy and/or distribute it,
5 dnl with or without modifications, as long as this notice is preserved.
7 AC_DEFUN([gl_FUNC_PIPE],
9 AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
11 AC_CHECK_FUNCS_ONCE([pipe])
12 if test $ac_cv_func_pipe != yes; then