/*
 * Sample program for getppid system call - No.64
 *
 * Name
 *     getpid, getppid - get process identification
 *
 * Synopsis
 *     #include <sys/types.h>
 *     #include <unistd.h>
 *
 *     pid_t getpid(void)
 *     pid_t getppid(void);
 *
 * Description
 *     getpid returns the process ID of the current process.
 *     (This is often used by routines that generate unique tem-
 *     porary file names.)
 *
 *     getppid returns the process ID of the parent of the cur-
 *     rent process.
 */

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

main()
{
	int pid;

	switch (pid = fork()) {
	case -1:
		perror("fork");
		break;
	case 0:
		printf("in the child process\n");
		printf("    current pid = %d\n", getpid());
		printf("    parent pid = %d\n", getppid());
		return 0;
		break;
	default:
		wait(NULL);
		printf("in the parent process\n");
		printf("    current pid = %d\n", getpid());
		break;
	}

	exit(0);
}