Quick demo of getpid (and getppid)

getpid.c

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

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

        p = getpid();
        pp = getppid();

        /* Cheap and cheerful, Linux only: pid_t is an int */
        printf("Pid: %d\nParent Pid: %d\n", (int) p, (int) pp);
        exit(0);
}