> thanks Michael.
>
> Where I can find doc about ENV variable (and others)
> on internet? (basically where is full spec on ruby
> langugage)
> I tried to find info on www.ruby-lang.org but
> "reference manual" doesn't say anything about ENV.

I use the following quite a lot
http://www.amazon.com/exec/obidos/tg/detail/-/0672320835/qid=1058302730/sr=8
-1/ref=sr_8_1/002-9482437-0819239?v=glance&s=books
http://www.amazon.com/exec/obidos/tg/detail/-/0201710897/ref=pd_sim_books_1/
002-9482437-0819239?v=glance&s=books

and online, http://www.rubycentral.com/book/index.html

For that particular issue, http://www.rubycentral.com/book/rubyworld.html