From: Stefano Crocco <stefano.crocco@...>
Date: 2007-02-06T08:51:53+09:00
Subject: Re: require statement clarification

Alle marted狸 6 febbraio 2007, Neville Franks ha scritto:
> For require "filename" if the filename doesn't include an extension is
> .rb assumed. I've been unable to find any documentation on this.
>
> Also the Ruby distribution telnet.rb source file includes:
> require "socket"
>
> however I'm unable to find any socket.rb file anywhere, only a socket.c
> So what does this file refer to?
>
> ---
> Neville Franks, http://www.getsoft.com http://www.surfulater.com

You can find the documentation you want with the command 'ri require'. At any 
rate, here's a summary: if the filename has a .rb extension, require loads it 
as a ruby source file. If it has the extension typical of libraries on that 
system (for example, .so on unix or .dll on windows), it loads it as a ruby 
extension. If the extension isn't specified, it tries adding the extensions 
to the filename, until it finds an existing file. 

Regarding socket, I have a socket.so file located 
in /usr/lib/ruby/1.8/i686-linux (This is on gentoo linux. I think other linux 
distributions may have it on different paths. I don't know about windows). 
This means that socket is a C extension. using require 'socket' will load the 
socket.so file.

I hope this helps

Stefano