1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
|
# truncate.m4 serial 2 -*- Autoconf -*-
dnl Copyright (C) 2017-2020 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_TRUNCATE],
[
AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
AC_CHECK_FUNCS_ONCE([truncate])
dnl AC_CHECK_FUNC is not enough here, because when compiling for Android 4.4
dnl or older with _FILE_OFFSET_BITS=64, truncate() is not declared. There
dnl is a function 'truncate' in libc, but it is unsuitable, because it takes
dnl only a 32-bit offset argument.
AC_CHECK_DECL([truncate], , , [[#include <unistd.h>]])
if test $ac_cv_have_decl_truncate = yes; then
m4_ifdef([gl_LARGEFILE], [
AC_REQUIRE([AC_CANONICAL_HOST])
case "$host_os" in
mingw*)
dnl Native Windows, and Large File Support is requested.
dnl The mingw64 truncate64() function is based on ftruncate64(),
dnl which is unreliable (it may delete the file, see
dnl <https://web.archive.org/web/20160425005423/http://mingw-w64.sourcearchive.com/documentation/2.0-1/ftruncate64_8c_source.html>).
dnl Use gnulib's ftruncate() and truncate() implementation instead.
REPLACE_TRUNCATE=1
;;
esac
], [
:
])
else
HAVE_DECL_TRUNCATE=0
if test $ac_cv_func_truncate = yes; then
dnl Avoid a conflict with the 'truncate' in libc.
REPLACE_TRUNCATE=1
fi
fi
])
# Prerequisites of lib/truncate.c.
AC_DEFUN([gl_PREREQ_TRUNCATE], [:])
|
