mystop.c

   1 /*
   2  * mystop.c - Another handy routine for testing your tiny shell
   3  *
   4  * usage: mystop <n>
   5  * Sleeps for <n> seconds and sends SIGTSTP to itself.
   6  *
   7  */
   8 #include <stdio.h>
   9 #include <unistd.h>
  10 #include <stdlib.h>
  11 #include <sys/types.h>
  12 #include <sys/wait.h>
  13 #include <signal.h>
  14
  15 int main(int argc, char **argv)
  16 {
  17     int i, secs;
  18     pid_t pid;
  19
  20     if (argc != 2) {
  21         fprintf(stderr, "Usage: %s <n>\n", argv[0]);
  22         exit(0);
  23     }
  24     secs = atoi(argv[1]);
  25
  26     for (i=0; i < secs; i++)
  27        sleep(1);
  28
  29     pid = getpid();
  30
  31     if (kill(-pid, SIGTSTP) < 0)
  32        fprintf(stderr, "kill (tstp) error");
  33
  34     exit(0);
  35
  36 }