09-28-2013
Thanks for the reply..sorry if the code is misleading but I was following an online tutorial to learn network programming.
All i want to do is to keep client in a loop until the user types "quit" so I will change while to do-while.
The client enters an infinite loop in which it queries the user which service is being requested. There are two options : echo and time.
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.
I hope it clears some part of what I want to implement.
So i thought of :
do
{
if user enters "echo"
then
it will fork off a child, doEcho() but what to do after that..I am not getting as
per the requirement like parents goes in infinte loop and all..
else if user enters "daytime"
then
it will fork off a child , doDayTime() and again the same.what to do/.
}while (user enters exit)
I guess I am following the right track???
Please guide me.
Thanks and Regards
Abhinav
Last edited by abhi1988sri; 09-28-2013 at 05:56 AM..
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LEARN ABOUT XFREE86
pthread_atfork
PTHREAD_ATFORK(3) Library Functions Manual PTHREAD_ATFORK(3)
NAME
pthread_atfork - register handlers to be called at fork(2) time
SYNOPSIS
#include <pthread.h>
int pthread_atfork(void (*prepare)(void), void (*parent)(void), void (*child)(void));
DESCRIPTION
pthread_atfork registers handler functions to be called just before and just after a new process is created with fork(2). The prepare han-
dler will be called from the parent process, just before the new process is created. The parent handler will be called from the parent
process, just before fork(2) returns. The child handler will be called from the child process, just before fork(2) returns.
One or several of the three handlers prepare, parent and child can be given as NULL, meaning that no handler needs to be called at the cor-
responding point.
pthread_atfork can be called several times to install several sets of handlers. At fork(2) time, the prepare handlers are called in LIFO
order (last added with pthread_atfork, first called before fork), while the parent and child handlers are called in FIFO order (first
added, first called).
To understand the purpose of pthread_atfork, recall that fork(2) duplicates the whole memory space, including mutexes in their current
locking state, but only the calling thread: other threads are not running in the child process. The mutexes are not usable after the fork
and must be initialized with pthread_mutex_init in the child process. This is a limitation of the current implementation and might or
might not be present in future versions.
RETURN VALUE
pthread_atfork returns 0 on success and a non-zero error code on error.
ERRORS
ENOMEM insufficient memory available to register the handlers.
AUTHOR
Xavier Leroy <Xavier.Leroy@inria.fr>
SEE ALSO
fork(2), pthread_mutex_lock(3), pthread_mutex_unlock(3).
LinuxThreads PTHREAD_ATFORK(3)