1  /* Test for freopen implementation.
       2     Copyright (C) 2000-2023 Free Software Foundation, Inc.
       3     This file is part of the GNU C Library.
       4  
       5     The GNU C Library is free software; you can redistribute it and/or
       6     modify it under the terms of the GNU Lesser General Public
       7     License as published by the Free Software Foundation; either
       8     version 2.1 of the License, or (at your option) any later version.
       9  
      10     The GNU C Library is distributed in the hope that it will be useful,
      11     but WITHOUT ANY WARRANTY; without even the implied warranty of
      12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      13     Lesser General Public License for more details.
      14  
      15     You should have received a copy of the GNU Lesser General Public
      16     License along with the GNU C Library; if not, see
      17     <https://www.gnu.org/licenses/>.  */
      18  
      19  #include <mcheck.h>
      20  #include <stdio.h>
      21  #include <stdlib.h>
      22  #include <wchar.h>
      23  
      24  
      25  int
      26  main (int argc, char *argv[])
      27  {
      28    FILE *fp;
      29  
      30    mtrace ();
      31  
      32    if (argc < 2)
      33      exit (1);
      34  
      35    fp = fopen (argv[1], "w");
      36    if (fp == NULL)
      37      {
      38        puts ("fopen failed: %m");
      39        exit (1);
      40      }
      41  
      42    fputs ("Hello world (mb)\n", fp);
      43  
      44    fp = freopen (argv[1], "a+", fp);
      45    if (fp == NULL)
      46      {
      47        puts ("freopen failed: %m");
      48        exit (1);
      49      }
      50  
      51    fputws (L"Hello world (wc)\n", fp);
      52  
      53    fclose (fp);
      54  
      55    return 0;
      56  }