defunct_test.c

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/wait.h>
#include <sys/types.h>

int	main(int argc, char const *argv[])
{
	int pid;

	for (int i = 0; i < 5; i++) {
		pid = fork();
		if (pid == 0)
		{
			printf("I am child %d\n", i);
			printf("Child %d is sleeping for 7 seconds...\n", i);
			printf("Let wait child %d with WNOHANG\n", i);
			sleep(7);
			printf("Child %d has finished its execution\nExiting child %d\n", i, i);

			if (i == 4)
			{
				printf("Now check up the process tree while the parent is sleeping!\n");
			}
			exit(0);
		}

		sleep(1);
		int status;
		waitpid(pid, &status, WNOHANG);
		printf("pid: %d\n", status);
		printf("wexitstatus: %d\n\n", WEXITSTATUS(status));
	}

	printf("I am the parent\n");
	printf("The parent is now sleeping for 100 seconds\n\n");
	sleep(100);
	return 0;
}