On rails?

[Gadget]

The Rails::ScriptRailsLoader module here defines two constants: RUBY and SCRIPT_RAILS. RUBY is the full path to your ruby executable, on a Snow Leopard system it’s /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/bin/ruby_. SCRIPTRAILS is simply script/rails_. When exec_scriptrails is invoked, this will attempt to exec the rails file in the script directory using the path to your Ruby executable, RUBY. If exec is invoked, the program will stop at this point. If the script/rails file doesn’t exist in the current directory, Rails will recurse upwards until it finds it by calling exec_script_rails from inside the Dir.chdir(".."). This is handy if you’re currently in one of the sub-directories of the rails application and wish to launch a server or a console.

Dunno if this site will help you out or not: http://guides.rubyonrails.org/initialization.html