Message passing from child to parent using pipes Post: 302857989

Sponsored Content

Special Forums IP Networking Message passing from child to parent using pipes Post 302857989 by abhi1988sri on Friday 27th of September 2013 11:42:17 PM

09-28-2013

Registered User

Message passing from child to parent using pipes

Hi,

I am trying my hand in networking programming in C, and got stuck in piping.

I was following some tutorial and did the forking like :

Code:

while (1) 
    {
        newsockfd = accept(sockfd, 
                (struct sockaddr *) &cli_addr, &clilen);
        if (newsockfd < 0)
        {
            perror("ERROR on accept");
            exit(1);
        }
        /* Create child process */
        pid = fork();
        if (pid < 0)
        {
            perror("ERROR on fork");
	    exit(1);
        }
        if (pid == 0)  
        {
            /* This is the client process */
            close(sockfd);
            doprocessing(newsockfd);
            exit(0);
        }
        else
        {
            close(newsockfd);
        }
    } /* end of while */

I want to have:

The client forks off a child. After the child is forked off, the parent process enters a second loop in which it continually reads and prints out status messages received from the child via a half-duplex pipe.
How to do the thing in bold?

Apologies , if it is a lame question..but how do we do that or some reference of the same would help me..

Regards

Abhinav

abhi1988sri

View Public Profile for abhi1988sri

Find all posts by abhi1988sri

10 More Discussions You Might Find Interesting

1. Programming

how to passing message along pipes??

Dear All, Would you tell me how I can passing a message along pipes? I have built a token ring connected with pipes, but I don't know how to pass the message along it through the command line... Thx. Yours, i-

2. Filesystems, Disks and Memory

How hard can it be? ps child/parent

:( Since I'm fairly new to the scene and don't have much experience in shell programming, I decided to check out the net for a useful script or two. What I'm looking for is a script that would let me enter a PID and then show the process tree associated with it. So it would display the (grand-)...

3. Programming

Implementing 2 pipes between a parent and child process

Hi all, I'm trying to write a program that has some data it wants to send through a filter program(in this case tr), and then recieve the output from that filter program. The way I'm trying to do it is by setting up two pipes between the programs and piping the data in through one pipe and back...

4. Shell Programming and Scripting

Parent/Child Processes

Hello. I have a global function name func1() that I am sourcing in from script A. I call the function from script B. Is there a way to find out which script called func1() dynamically so that the func1() can report it in the event there are errors? Thanks

5. Shell Programming and Scripting

Passing a variable from a child script back to the parent

Hi I have written a script using ftp to get files from one server and copy them to 2 dirrerent servers. I wish to call this script from a parent script that will check the number of files copied and run a check sum for each file. As the filenames for the files in the get portion of the script...

6. Programming

IPC - pipes between parent and child process

Hi guys, I'm having some problem here, I'm studying pipes, and i want to create a shell in C and at this point a don't want to use semaphores, instead I want to use tricks. Straight to the doubt: I've a parent and a child process, and both of them has some code to execute, and the child process...

7. Homework & Coursework Questions

Need help with deleting child�s parent and child subprocess

1. The problem statement, all variables and given/known data: I need to make an program that in a loop creates one parent and five children with fork(). The problem i'm trying to solve is how to delete the parent and child of the child�s process. 2. Relevant commands, code, scripts,...

8. Shell Programming and Scripting

forking a child process and kill its parent to show that child process has init() as its parent

Hi everyone i am very new to linux , working on bash shell. I am trying to solve the given problem 1. Create a process and then create children using fork 2. Check the Status of the application for successful running. 3. Kill all the process(threads) except parent and first child...

9. Programming

Child threads communicating with main thread via pipes

I have a simple client/server program I am using for learning purposes. I have it setup so that after server is setup and listening it than goes into a loop where it accepts incoming client connections. After each connection, the client socket is than passed to a thread routine where it can be...

10. Shell Programming and Scripting

Passing key column from parent to child records

Hi Forum. I have this challenging issue that I'm hoping someone can help me. I have a file that contains 3 different types of segments (AM00, AM01, AM32) in a hierarchy structure and I want to be able to pass the column key from the parent record to the children records. AM00 - parent key:...

LEARN ABOUT DEBIAN

sockets.socketpair

Sockets.socketPair(3kaya)				       Kaya module reference					 Sockets.socketPair(3kaya)

NAME

       Sockets::socketPair - Create a joined pair of sockets

SYNOPSIS

       Pair<Socket, Socket> socketPair( )

DESCRIPTION

       This  function  creates	a pair of sockets that can be used for bi-directional communication. The most common use of this is for setting up
       communications between a process and its Posix.fork(3kaya) ()ed child - each process closes one of the sockets after the fork.

    sockets = socketPair();
    pid = fork();
    if (pid == 0) {
    // child process
      close(sockets.fst);
      // do something
    } else {
      close(sockets.snd);
      // do something else
    }

AUTHORS

       Kaya standard library by Edwin Brady, Chris Morris and others (kaya@kayalang.org). For further information see http://kayalang.org/

LICENSE

       The Kaya standard library is free software; you can redistribute it and/or modify it under the terms  of  the  GNU  Lesser  General  Public
       License (version 2.1 or any later version) as published by the Free Software Foundation.

RELATED

       Sockets.Socket(3kaya)
       Sockets.close(3kaya)
       Posix.fork(3kaya)

Kaya								   October 2012 					 Sockets.socketPair(3kaya)

10 More Discussions You Might Find Interesting

1. Programming

how to passing message along pipes??

Discussion started by: iminus

2. Filesystems, Disks and Memory

How hard can it be? ps child/parent

Discussion started by: velde046

3. Programming

Implementing 2 pipes between a parent and child process

Discussion started by: bwgoudey

4. Shell Programming and Scripting

Parent/Child Processes

Discussion started by: yoi2hot4ya