tcp server basic idea
--
server have a socket open for connection from client
Accept connection from client
Fork a child process (at server side)
Handle the connection to child, then close parent process.
Child process can do whatever need to do with client While parent process can deal with new connections.

-- simple code for parent and child
# After fork, two identical processes created. 
# parent process can continue process upcoming client connections, 
# while child process deal with each request.

if( !defined($child_pid = fork) ) {
   printf( "Cannot fork: $!\n" );
}
elsif( $child_pid ) { # parent process. If I have a child PID, then I must be the parent
   printf( "New server started with PID: $child_pid, will be recycled after it's reap\n" );
}
else { # else I'm the worker child. I am the child
   #
   # do real stuff here
   #
   exit;
}