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

int main(){
	int pid;
	int pfd[2];
	int i;
	
	pipe(pfd);
	
	pid = fork();
	
	if(pid==0){ /*CHILD*/
		
		for(i = 0; i < 5; i++){
			write(pfd[1], "Hallo", 5);
			sleep(3);	
		}	
		
		exit(0);
	}
	
	/*PARENT*/
	close(pfd[1]);
	
	while(1){
		fd_set rd; /*Liste der zu beobachtenden FDs*/
		char buf[6];
		int res, r;
		
		FD_ZERO(&rd); /*Liste leeren*/
		FD_SET(pfd[0], &rd); /*pfd[0] in die Liste aufnehmen*/
		
		r = select(pfd[0] + 1, &rd, NULL, NULL, NULL);
		
		if(r<=0) perror("select");
			
		res = read(pfd[0], buf, 5);
		
		if(res == 0) break; /*res == 0 => EOF*/
			
		buf[res] = '\0';
		printf("%s\n", buf);
		
	}
	
	return 0;
}