1 /* Regression test for reported old bug that errno is clobbered
2 by the first successful output to a stream on an unseekable object.
3 Copyright (C) 1995-2021 Free Software Foundation, Inc.
4 This file is part of the GNU C Library.
5
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
10
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
15
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, see
18 <https://www.gnu.org/licenses/>. */
19
20 #include <errno.h>
21 #include <stdio.h>
22 #include <unistd.h>
23
24 int
main(void)25 main (void)
26 {
27 int fd[2];
28 FILE *f;
29
30 /* Get a stream that cannot seek. */
31
32 if (pipe (fd))
33 {
34 perror ("pipe");
35 return 1;
36 }
37 f = fdopen (fd[1], "w");
38 if (f == NULL)
39 {
40 perror ("fdopen");
41 return 1;
42 }
43
44 errno = 0;
45 if (fputs ("fnord", f) == EOF)
46 {
47 perror ("fputs");
48 return 1;
49 }
50
51 if (errno)
52 {
53 perror ("errno gratuitously set -- TEST FAILED");
54 return 1;
55 }
56
57 puts ("Test succeeded.");
58 return 0;
59 }
60