When the subject is about ruby reference guide I always use this:
http://www.ruby-doc.org/core/classes/File.html

(The File module in you particular case)

Paul Lutus wrote:
> Snoopy Dog wrote:
>
> / ...
>
> > So a new question here:  How do I find out what methods exist for an
> > object?
>
> puts objectname.methods
>
> >
> > eg:  For the File object, how can I find out about the open, file?,
> > close, and other methods (as well as their syntax).
>
> You can get the method names as above, but to learn how to use them, you
> will have to consult the documentation.
>
> >
> > Also what references should I be looking at other than this forum?
>
> http://www.ruby-lang.org/en/documentation/
> 
> -- 
> Paul Lutus
> http://www.arachnoid.com