#include <sys/types.h>#include <unistd.h>#include <stdio.h>int main(){    pid_t pid;    char *message;    int n;    printf("fork program starting\n");    pid = fork();    switch(pid)     {    case -1:        perror("fork failed");        exit(1);    case 0:        message = "This is the child";        n = 3;        break;    default:        message = "This is the parent";        n = 5;        break;    }    for(; n > 0; n--) {        puts(message);        sleep(1);    }    exit(0);}