ipc/fork_mult.c

   1 /* compile with:
   2    gcc fork_mult.c -o fork_mult -Wall -W -Wextra -ansi -pedantic */
   3
   4 #include <stdio.h>
   5 #include <stdlib.h>
   6 #include <unistd.h>
   7 #include <sys/wait.h>
   8
   9 #define NUM_CHILDS 5
  10
  11 int main(void)
  12 {
  13     pid_t pid[NUM_CHILDS];
  14     int i, retval;
  15
  16     for (i = 0; i < NUM_CHILDS; i++) {
  17         if ((pid[i] = fork()) < 0) {    /* fork error */
  18             perror("fork");
  19             exit(EXIT_FAILURE);
  20         }
  21
  22         else if (pid[i] > 0) {          /* parent process */
  23             wait(&retval);
  24         }
  25
  26         else {                          /* child process (pid = 0) */
  27             printf("Child[%d] = %d\n", i, getpid());
  28
  29             /* break, or else every child will spawn it's own children */
  30             break;
  31         }
  32     }
  33    return EXIT_SUCCESS;
  34 }