1  /* Test of fwrite() function, adapted from gnulib-tests in grep.
       2     Copyright (C) 2011-2023 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  
      24  static int
      25  do_test (void)
      26  {
      27    char tmpl[] = "/tmp/tst-fwrite-error.XXXXXX";
      28    int fd = mkstemp (tmpl);
      29    if (fd == -1)
      30      {
      31        printf ("mkstemp failed with errno %d\n", errno);
      32        return 1;
      33      }
      34    FILE *fp = fdopen (fd, "w");
      35    if (fp == NULL)
      36      {
      37        printf ("fdopen failed with errno %d\n", errno);
      38        return 1;
      39      }
      40  
      41    char buf[] = "world";
      42    setvbuf (fp, NULL, _IONBF, 0);
      43    close (fd);
      44    unlink (tmpl);
      45    errno = 0;
      46  
      47    int ret = fwrite (buf, 1, sizeof (buf), fp);
      48    if (ret != 0)
      49      {
      50        printf ("fwrite returned %d\n", ret);
      51        return 1;
      52      }
      53    if (errno != EBADF)
      54      {
      55        printf ("Errno is not EBADF: %d\n", errno);
      56        return 1;
      57      }
      58    if (ferror (fp) == 0)
      59      {
      60        printf ("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"