kc3-lang/gnulib/tests/test-select-stdin.c

• Show log

  Commit

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

  maint: run 'make update-copyright'
  

Download

• tests/test-select-stdin.c

• /* Test of select() substitute, reading from stdin.
     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/>.  */
  
  /* Written by Bruno Haible <bruno@clisp.org>, 2008.  */
  
  #include <config.h>
  
  #include <stdio.h>
  #include <stdlib.h>
  #include <sys/select.h>
  #include <sys/time.h>
  #include <unistd.h>
  
  #include "macros.h"
  
  int
  main (void)
  {
    printf ("Applying select() from standard input. Press Ctrl-C to abort.\n");
    for (;;)
      {
        struct timeval before;
        struct timeval after;
        unsigned long spent_usec;
        fd_set readfds;
        struct timeval timeout;
        int ret;
  
        gettimeofday (&before, NULL);
  
        FD_ZERO (&readfds);
        FD_SET (0, &readfds);
        timeout.tv_sec = 0;
        timeout.tv_usec = 500000;
        ret = select (1, &readfds, NULL, NULL, &timeout);
  
        gettimeofday (&after, NULL);
        spent_usec = (after.tv_sec - before.tv_sec) * 1000000
                     + after.tv_usec - before.tv_usec;
  
        if (ret < 0)
          {
            perror ("select failed");
            exit (1);
          }
        if ((ret == 0) != ! FD_ISSET (0, &readfds))
          {
            fprintf (stderr, "incorrect return value\n");
            exit (1);
          }
        if (ret == 0)
          {
            if (spent_usec < 250000)
              {
                fprintf (stderr, "returned too early\n");
                exit (1);
              }
            /* Timeout */
            printf (".");
            ASSERT (fflush (stdout) == 0);
          }
        else
          {
            char c;
  
            printf ("Input available! Trying to read 1 byte...\n");
            ASSERT (read (0, &c, 1) == 1);
          }
      }
  }
  

Download