/*
 * Example demonstrating fork(), getpid(), and getppid() 
 */
#include <stdio.h>

main()
{
    int pid;   /* hold child's process-id in parent */

    printf("Just one process so far.  My pid is %d\n", getpid());
    fflush(stdout);  /* ensuring stdout buffer isn't duplicated in fork() */

    switch ( pid = fork() )
    {
        case 0: /* child */
            printf("I'm the child, parent has pid %d\n", getppid());
            break;

        case -1: /* error: resources must be exceeded */
            printf("Fork returned error code, no child\n");
            break;

        default: /* parent */
            printf("I'm the parent, child has pid %d\n", pid);
            break;
    }
}