thetwig 0 Newbie Poster

hey guys.. I'm trying to create a bunch of children where the parent creates child1, and child1 creates child2 and the parent creates child3 using fork()... and I'm supposed to pass a message through using a pipe, but when I pass from child2 to child3 I have to use a fifo file.. all are working except for the fifo file... so all of them print fine except for child3:

Enter String: kaka
I am parent.
Parent: kaka

I am child1.
Child1: kaka

I am child2.
Child2: kaka

I am child3.
Child3:

#include <stdio.h>
#include <unistd.h>
#include <sys/types.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <string.h>
#include <fcntl.h>

/*#include <sys/wait.h>*/


int main(void)
{
	int     unnamed[2], nbytes, flag, i;
	pid_t   pid;
	char    string[128];
	char    readbuffer[80];

	printf("Enter String: ");
	fgets(string, 127, stdin);
	
	mkfifo ("file", S_IXGRP);
	i = open("file", O_RDWR|O_NONBLOCK);
	
	pipe(unnamed);

	if((pid = fork()) == -1)
	{	perror("Fork error.\n");
		exit(1);
	}

	if(pid == 0)	/*child1*/
	{	printf("I am child1.\n");
		nbytes = read(unnamed[0], readbuffer, sizeof(readbuffer));
		printf("Child1: %s\n", readbuffer);
		write(unnamed[1], readbuffer, (strlen(readbuffer)+1));
		
		if((pid = fork()) == -1)
		{	perror("Fork error.\n");
			exit(1);
		}
		
		if(pid == 0)	/*child2*/
		{	printf("I am child2.\n");
			nbytes = read(unnamed[0], readbuffer, sizeof(readbuffer));
			printf("Child2: %s\n", readbuffer);
			write(i, readbuffer, (strlen(readbuffer)+1));
		}
		else
		{	wait(&flag);
		}


	}
	else	/*parent*/
	{	printf("I am parent.\n");
		write(unnamed[1], string, (strlen(string)+1));
		printf("Parent: %s\n", string);
		
		
		if((pid = fork()) == -1)
		{	perror("Fork error.\n");
			exit(1);
		}
		
		
		if(pid == 0)	/*child3*/
		{	printf("I am child3.\n");
			nbytes = read(i, readbuffer, sizeof(readbuffer));
			printf("Child3: %s\n", readbuffer);
			write(unnamed[1], readbuffer, (strlen(readbuffer)+1));
		}
		
		else
		{	close(unnamed[0]);
			close(unnamed[1]);
		}

	}
        
        return(0);
}

Why doesn't it print? Thanks in advance.

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