1  /* Copyright (C) 2003-2023 Free Software Foundation, Inc.
       2     This file is part of the GNU C Library.
       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 <error.h>
      20  #include <signal.h>
      21  #include <stdlib.h>
      22  #include <stdio.h>
      23  
      24  volatile int count;
      25  
      26  void
      27  sh (int sig)
      28  {
      29    ++count;
      30  }
      31  
      32  int
      33  main (void)
      34  {
      35    struct sigaction sa;
      36    sa.sa_handler = sh;
      37    sigemptyset (&sa.sa_mask);
      38    sa.sa_flags = 0;
      39    if (sigaction (SIGUSR1, &sa, NULL) < 0)
      40      {
      41        printf ("sigaction failed: %m\n");
      42        exit (1);
      43      }
      44    if (raise (SIGUSR1) < 0)
      45      {
      46        printf ("first raise failed: %m\n");
      47        exit (1);
      48      }
      49    if (raise (SIGUSR1) < 0)
      50      {
      51        printf ("second raise failed: %m\n");
      52        exit (1);
      53      }
      54    if (count != 2)
      55      {
      56        printf ("signal handler not called 2 times\n");
      57        exit (1);
      58      }
      59    exit (0);
      60  }