On Fri, 2008-12-19 at 03:04 +0530, Chaitanya Gupta wrote:

Hi,

I can't seem to find the IOLib documentation -- there's no link to it on the project page at common-lisp.net.

I want to try out the I/O multiplexer but I am clueless on how to go about working with it. Any help on this (or pointer to the doc location) would be great.

Cheers, Chaitanya

Hi, I've written a simple HTTP server that uses IOLib. Maybe it can help one figure out how IOLib works or can be used:

http://common-lisp.net/~lnostdal/programming/lisp/sw-http/

Basically start by creating a server socket (server.lisp):

* make-socket (iolib) * ..and make it non-blocking * set-io-handler (iolib) * set-error-handler (iolib)

set-io-handler (iolib) dispatches to the handle-socket-event (sw-http, server.lisp) callback which calls connection-start-reading (sw-http, connection.lisp).

connection-start-reading sets up a new callback, connection-handle (sw-http, connection.lisp) by calling set-io-handler (iolib) on the client socket. It also makes sure the client socket is made non-blocking.

connection-handle has a (case event ..) form which leads to request-handle (sw-http, request-incoming.lisp) for :read events.

Ok, that's basically it with regards to the multiplexing stuff really.

This should be familiar stuff quite similar to what's going on in C on a "concept" level. You keep reading until reading would block then make a note of where you are now then return to the event loop (the blocking event-dispatch call/loop in server.lisp) so the next waiting event in line can be served.