#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/wait.h>
    
void do_child(void)
{
        printf("This is child(pid=%d).\n", getpid());
        exit(2);
}
    
int main(void)
{
        int child, status;
    
        if ((child = fork()) < 0) {
                perror("fork");
                exit(1);
        }
    
        if (child == 0) {
                do_child();
        } else {
                if (wait(&status) < 0) {
                        perror("wait");
                        exit(1);
                }
                printf("The child (pid=%d) exited with status(%d).\n",
                       child, WEXITSTATUS(status));
        }

        return 0;
}