1/* Test of fwrite() function, adapted from gnulib-tests in grep.
2 Copyright (C) 2011-2024 Free Software Foundation, Inc.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <https://www.gnu.org/licenses/>. */
17
18#include <errno.h>
19#include <fcntl.h>
20#include <unistd.h>
21#include <stdio.h>
22#include <stdlib.h>
23
24static int
25do_test (void)
26{
27 char tmpl[] = "/tmp/tst-fwrite-error.XXXXXX";
28 int fd = mkstemp (template: tmpl);
29 if (fd == -1)
30 {
31 printf (format: "mkstemp failed with errno %d\n", errno);
32 return 1;
33 }
34 FILE *fp = fdopen (fd, "w");
35 if (fp == NULL)
36 {
37 printf (format: "fdopen failed with errno %d\n", errno);
38 return 1;
39 }
40
41 char buf[] = "world";
42 setvbuf (stream: fp, NULL, _IONBF, n: 0);
43 close (fd: fd);
44 unlink (name: tmpl);
45 errno = 0;
46
47 int ret = fwrite (buf, 1, sizeof (buf), fp);
48 if (ret != 0)
49 {
50 printf (format: "fwrite returned %d\n", ret);
51 return 1;
52 }
53 if (errno != EBADF)
54 {
55 printf (format: "Errno is not EBADF: %d\n", errno);
56 return 1;
57 }
58 if (ferror (stream: fp) == 0)
59 {
60 printf (format: "ferror not set\n");
61 return 1;
62 }
63
64 return 0;
65}
66
67#define TEST_FUNCTION do_test ()
68#include "../test-skeleton.c"
69

source code of glibc/libio/tst-fwrite-error.c