gistfile1.c

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/wait.h>
 
 
int main(void) {
	int status, w;
	pid_t pid;
 
	pid = fork();
 
	if (pid == -1)  /* Fehler! */
	{
		perror ("fork");  /* gibt den entsprechenden Fehlercode aus (globale Variable "errno") */
		exit(EXIT_FAILURE);
	}
 
	if (pid == 0)	/* Child */
	{
		printf ("\t\tChild says: My PID is %lu so I am.\n", (unsigned long) getpid());
		fflush (stdout);
		sleep (20);        /* 5 Sekunden warten; Prozess wird in den Zustand "Blockiert" versetzt */
		printf ("\t\tChild says: Exit in one second...\n");
		fflush (stdout);
		sleep(1);
		exit (EXIT_SUCCESS);
	}
	else	/* Parent */
	{
		printf ("Parent says: I'm waiting for PID %d...\n", pid);
		fflush (stdout);
		w = waitpid (pid, &status, 0);		/* Warte, bis Kind-Prozess beendet */
		printf ("Parent says: Child exited with status %d.\n", status);
		fflush (stdout);
	}
 
	return EXIT_SUCCESS;
}