From: Tim Hunter <TimHunter@...>
Date: 2008-07-06T07:10:33+09:00
Subject: Re: irb not recognized in windows command line

Bert Ameche wrote:
> I forgot to mention that 'ruby -v' does not work either - get the same 
> message "ruby" is not recognized.

Your path has nothing to do specifically with Ruby. It's part of the way 
Windows command prompt windows work. Your path is a list of directories. 
When you enter a command at a command prompt, if the command is not 
built into Windows itself (like dir, or chdir), then Windows searches 
for the command in the directories listed in your path. You can make 
temporary changes to your path using the SET PATH= command, or permanent 
changes via the System tab in Control Panel.

When you install Ruby using the One-Click Installer, the installer 
changes your path to include the directory in which it installs the ruby 
and irb commands. That change does not affect existing command prompt 
windows, it only affects command prompt windows that you start after 
running the One-Click Installer. If you continue to use an command 
prompt window that was open before you used the One-Click Installer, 
then that window is still using the old path and therefore can't find 
ruby or irb.

If you haven't started a new command prompt window since you installed 
Ruby, close all of the command prompt windows you have open now and 
start a new one. The new path will be in effect and you should be able 
to run ruby and irb.

Here's more information about the path. It's for WinXP but I think 
things are very similar in Vista: 
http://www.computerhope.com/issues/ch000549.htm.


-- 
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RMagick 2: http://rmagick.rubyforge.org/rmagick2.html