From: Joel VanderWerf <joelvanderwerf@...>
Date: 2010-07-28T08:45:32+09:00
Subject: Re: Which Ruby is in use?

Hassan Schroeder wrote:
> On Tue, Jul 27, 2010 at 3:52 PM, Joel VanderWerf
> <joelvanderwerf@gmail.com> wrote:
> 
>>>>>> File.join *Config::CONFIG.values_at("bindir", "ruby_install_name")
>>>> => "/usr/local/bin/ruby"
>>> Works in a Rails console, but not a Ruby program. But thanks, now
>>> that I consider it I should be able to work with that  :-)
>> Hm, that's surprising. I tested it in ruby and jruby programs. What's the
>> problem?
> 
> ripple:~$ cat foo.rb
> puts File.join *Config::CONFIG.values_at("bindir", "ruby_install_name")
> ripple:~$ ruby foo.rb
> foo.rb:1: uninitialized constant Config (NameError)
> ripple:~$ jruby foo.rb
> foo.rb:1: uninitialized constant Config (NameError)
> ripple:~$
> 

You must require 'rbconfig':

$ ruby -v -rrbconfig -e 'p File.join(*Config::CONFIG.values_at("bindir", 
"ruby_install_name"))'
ruby 1.8.7 (2010-06-23 patchlevel 299) [x86_64-linux]
"/usr/local/bin/ruby"