#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

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

    switch (pid = fork()) {

    case -1: {
        perror("fork");
        _exit(EXIT_FAILURE);
    }
        
    case 0: {
        printf("I'm the child. My pid is %u\n", getpid());
        _exit(EXIT_SUCCESS);
    }
        
    default: { 
        printf("I'm the parent. My pid is %u, my child's pid is %u\n", 
               getpid(), pid);
    }

    }
    
    return 0;
}