🚀 go-pugleaf

In article <1993Jan26.222115.28187@slate.mines.colorado.edu>, iarit@slate.mines.colorado.edu (ARIT ISMAIL) writes:
|> Hi,
|> 
|> I don't know if this is the right place to post this, but
|> I need some help about writing a simple client/server program.
|> 
|> Here is what I am trying to do;
|> 
|> I want to write a program that will accept connections from
|> other programs and will communicate with them without forking.
|> I don't want to fork because the info should be generated on one
|> program, send to server and the server has to respond to every
|> program connected with the same info( if I fork, how  can I transfer
|> that info to child?).
|> 
|>   main                     main
|>   client <--> server <--> client
|>                 |
|>                 |
|>          _______________________________
|>          |         |        |        |
|>          v         v        v        v
|>        client1  client2  client3     ......
|> 
|> (main clients generate the info)
|> I know this is not an easy thing to do, but actually, I am having
|> problems with accept(..);
|> can I do something like this;
|> 
|> while(1)
|> {
|>  check_new_connection(); /* how can I check if there is any new
|> connection
|>                            without waiting, as far as I know accept(..)
|>                            blocks you 'till you get some connection*/
|>  check_clients();       /* I can do these, no problem. read if there is
|>                            any new info */
|>  if(thereIsNewInfo)
|>    inform_clients();     /* if I can create a list of handles for clients
|>                            this is no big deal */
|> 
|> }
|> My problem is getting new connections without waiting.
	If your problem is only about having a non-blocking "accept()", then
you mark the socket as non-blocking. If you then try accept() , you will see
that accept will accept the connection, if there is a pending connection request.
On the other hand if no pending connections are there, then accept 
will return immediately with an error (I think EWOULDBLOCK).
You can use fcntl (O_NDELAY or O_NONBLOCK) for the server socket to get this
feature.

|> 
|> I appreciate any help.
|> 
|> iarit@slate.mines.colorado.edu
-raj
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