3 dnl Copyright (C) 2011-2024 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_ONCE([gl_SYS_UIO_H],
10 AC_REQUIRE([gl_SYS_UIO_H_DEFAULTS])
11 dnl <sys/uio.h> is always overridden, because of GNULIB_POSIXCHECK.
12 gl_CHECK_NEXT_HEADERS([sys/uio.h])
13 if test $ac_cv_header_sys_uio_h = yes; then
18 AC_SUBST([HAVE_SYS_UIO_H])
21 # gl_SYS_UIO_MODULE_INDICATOR([modulename])
22 # sets the shell variable that indicates the presence of the given module
23 # to a C preprocessor expression that will evaluate to 1.
24 # This macro invocation must not occur in macros that are AC_REQUIREd.
25 AC_DEFUN([gl_SYS_UIO_MODULE_INDICATOR],
27 dnl Ensure to expand the default settings once only.
28 gl_SYS_UIO_H_REQUIRE_DEFAULTS
29 gl_MODULE_INDICATOR_SET_VARIABLE([$1])
30 dnl Define it also as a C macro, for the benefit of the unit tests.
31 gl_MODULE_INDICATOR_FOR_TESTS([$1])
34 # Initializes the default values for AC_SUBSTed shell variables.
35 # This macro must not be AC_REQUIREd. It must only be invoked, and only
36 # outside of macros or in macros that are not AC_REQUIREd.
37 AC_DEFUN([gl_SYS_UIO_H_REQUIRE_DEFAULTS],
39 m4_defun(GL_MODULE_INDICATOR_PREFIX[_SYS_UIO_H_MODULE_INDICATOR_DEFAULTS], [
41 m4_require(GL_MODULE_INDICATOR_PREFIX[_SYS_UIO_H_MODULE_INDICATOR_DEFAULTS])
42 AC_REQUIRE([gl_SYS_UIO_H_DEFAULTS])
45 AC_DEFUN([gl_SYS_UIO_H_DEFAULTS],