kc3-lang/gnulib/tests/test-fflush2.c

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• Hash : 7b089321
  Author :
  Date : 2025-01-01T09:24:36
  

  maint: run 'make update-copyright'
  

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• tests/test-fflush2.c

• /* Test of POSIX compatible fflush() function.
     Copyright (C) 2008-2025 Free Software Foundation, Inc.
  
     This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
     the Free Software Foundation, either version 3 of the License, or
     (at your option) any later version.
  
     This program 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 General Public License for more details.
  
     You should have received a copy of the GNU General Public License
     along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  
  #include <config.h>
  
  #include <stdio.h>
  
  #include "binary-io.h"
  #include "macros.h"
  
  int
  main (int argc, char **argv)
  {
    int c;
  
    /* Avoid the well-known bugs of fflush() on streams in O_TEXT mode
       on native Windows platforms.  */
    set_binary_mode (0, O_BINARY);
  
    if (argc > 1)
      switch (argv[1][0])
        {
        case '1':
          /* Check fflush after a backup ungetc() call.  This is case 1a in
             terms of
             <https://lists.gnu.org/r/bug-gnulib/2008-03/msg00131.html>,
             according to the Austin Group's resolution on 2009-01-08.  */
  
          c = fgetc (stdin);
          ASSERT (c == '#');
  
          c = fgetc (stdin);
          ASSERT (c == '!');
  
          /* Here the file-position indicator must be 2.  */
  
          c = ungetc ('!', stdin);
          ASSERT (c == '!');
  
          fflush (stdin);
  
          /* Here the file-position indicator must be 1.  */
  
          c = fgetc (stdin);
          ASSERT (c == '!');
  
          c = fgetc (stdin);
          ASSERT (c == '/');
  
          return test_exit_status;
  
        case '2':
          /* Check fflush after a non-backup ungetc() call.  This is case 2a in
             terms of
             <https://lists.gnu.org/r/bug-gnulib/2008-03/msg00131.html>,
             according to the Austin Group's resolution on 2009-01-08.  */
          /* Check that fflush after a non-backup ungetc() call discards the
             ungetc buffer.  This is mandated by POSIX
             <https://pubs.opengroup.org/onlinepubs/9699919799/functions/fflush.html>:
               "...any characters pushed back onto the stream by ungetc()
                or ungetwc() that have not subsequently been read from the
                stream shall be discarded..."  */
  
          c = fgetc (stdin);
          ASSERT (c == '#');
  
          c = fgetc (stdin);
          ASSERT (c == '!');
  
          /* Here the file-position indicator must be 2.  */
  
          c = ungetc ('@', stdin);
          ASSERT (c == '@');
  
          fflush (stdin);
  
          /* Here the file-position indicator must be 1.  */
  
          c = fgetc (stdin);
          ASSERT (c == '!');
  
          c = fgetc (stdin);
          ASSERT (c == '/');
  
          return test_exit_status;
        }
  
    return 1;
  }
  

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