/* Regression test for reported old bug that errno is clobbered by the first successful output to a stream on an unseekable object. Copyright (C) 1995-2015 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, see <http://www.gnu.org/licenses/>. */ #include <errno.h> #include <stdio.h> #include <unistd.h> int main (void) { int fd[2]; FILE *f; /* Get a stream that cannot seek. */ if (pipe (fd)) { perror ("pipe"); return 1; } f = fdopen (fd[1], "w"); if (f == NULL) { perror ("fdopen"); return 1; } errno = 0; if (fputs ("fnord", f) == EOF) { perror ("fputs"); return 1; } if (errno) { perror ("errno gratuitously set -- TEST FAILED"); return 1; } puts ("Test succeeded."); return 0; }