Waiting for all child processes before parent resumes execution UNIX

Instead of calling waitpid in the signal handler, why not create a loop after you have forked all the processes as follows:

while (pid = waitpid(-1, NULL, 0)) {
   if (errno == ECHILD) {
      break;
   }
}

The program should hang in the loop until there are no more children. Then it will fall out and the program will continue. As an additional bonus, the loop will block on waitpid while children are running, so you don’t need a busy loop while you wait.

You could also use wait(NULL) which should be equivalent to waitpid(-1, NULL, 0). If there’s nothing else you need to do in SIGCHLD, you can set it to SIG_IGN.

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