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# 1  
Old 09-26-2010
Question Help With FIFO problem...
=server.c=
Code:
#include <stdio.h>

#include <stdlib.h>

#include <sys/stat.h>

#include <sys/types.h>

#include <unistd.h>

#include <errno.h>

#include <fcntl.h>

#include <string.h>

#include <signal.h>
#define MSGSIZE 50


char *fifo1="fifo1";
char *fifo2="fifo2";



main()

{

    	char msgbuf[MSGSIZE];

    	pid_t pid;
	int fd1,fd2;



	system("clear");

	printf("************** SERVER SIDE ***************\n");

     	if ((mkfifo(fifo1, 0666) == -1) && (errno != EEXIST))

	{

            	perror("Error creating the named pipe");

            	exit (1);

        }

      

        if ((mkfifo(fifo2, 0666) == -1) && (errno != EEXIST)) 

	{

            	perror("Error creating the named pipe");

            	exit (1);

        }

	if((fd2=open(fifo2, O_RDONLY|O_NONBLOCK))<0)
		perror("fifo2 open failed");

	if((fd1=open(fifo1, O_WRONLY|O_NONBLOCK))<0)
		perror("fifo1 open failed");

 	pid = fork();
	

//loop:

    	if (pid < 0) 

	{

		//failure in creating a child

        	perror ("fork");

    	  	exit(2);

    	}



    	else if (pid == 0) 

	{
		if(read(fd2, msgbuf, MSGSIZE+1)<0)
			perror("Message read failed");
		printf("Received message: %s", msgbuf);

       	}



    	else

	{	if(fgets(msgbuf,MSGSIZE, stdin) != NULL) 

		{
			if(write(fd1, msgbuf, MSGSIZE+1)<0)
				perror("Message write failed");
		}
	}

    	

//	goto loop;

=client.c=
Code:
#include <stdio.h>

#include <stdlib.h>

#include <sys/stat.h>

#include <sys/types.h>

#include <unistd.h>

#include <errno.h>

#include <fcntl.h>

#include <string.h>

#include <signal.h>
#define MSGSIZE 50

char *fifo1="fifo1";
char *fifo2="fifo2";

 

main()

{

       	char msgbuf[MSGSIZE];
	int fd1,fd2;

    	pid_t pid;



	system("clear");

	printf("************** CLIENT SIDE ***************\n");

        if ((mkfifo(fifo1, 0666) == -1) && (errno != EEXIST)) 

	{

            	perror("Error creating the named pipe");

            	exit (1);

        }



        if ((mkfifo(fifo2, 0666) == -1) && (errno != EEXIST)) 

	{

            perror("Error creating the named pipe");

            exit (1);

        }

	if((fd2=open(fifo1, O_WRONLY|O_NONBLOCK))<0)
		perror("fifo1 open failed");

	if((fd1=open(fifo2, O_RDONLY|O_NONBLOCK))<0)
		perror("fifo2 open failed");


	pid = fork(); 

//loop:

    	if (pid < 0) 

	{

        	//failure in creating a child

        	perror ("fork");

        	exit(2);

    	}



    	else if (pid == 0) 

	{

 		if(read(fd1, msgbuf, MSGSIZE+1)<0)
			perror("message read failed");
		printf("Received message: %s", msgbuf);

    	}

  

  	else

	{
		if(fgets(msgbuf,MSGSIZE, stdin) != NULL) 

		{
			if(write(fd2, msgbuf, MSGSIZE+1)<0)
				perror("Message write failed");
		}

        	

    	}

 //   goto loop;
}

The output is weird and i cant figure out why.
Can someone show me what is the problem?
Last edited by Scott; 09-26-2010 at 07:03 AM.. Reason: Please use code tags
# 2  
Old 09-26-2010
Admitted homework. Thread closed.
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