Gem install problem - II

Ruby
1
Thinking that maybe I should install manually from a downloaded rubygems, I uninstall it again, then download rubygems-1.0.1.tgz from rubyforge, unpack it, and issue...

:/$ ruby setup.rb

I get a glorious pile of output, of which these are the first two lines:

    install -c -m 0644 rubygems/rubygems_version.rb /usr/local/lib/site_ruby/1.8/rubygems/rubygems_version.rb
    install -c -m 0644 rubygems/dependency_list.rb /usr/local/lib/site_ruby/1.8/rubygems/dependency_list.rb

Reading through all of this, I nothing that looks like something went badly wrong - except this:
    Skipping RDoc generation, /usr/lib/ruby/gems/1.8/doc not writable
    Set the GEM_HOME environment variable if you want RDoc generated    
How do I do that?

All of this is happening in a console launched in my user account Desktop folder. Still there, I decide to test the install, as before, and issue
:/$ gem help

I get...
:/$ The program 'gem' is currently not installed.  You can install it by typing:
:/$ sudo apt-get install rubygems

How can this be? Didn't I just install it? It sure looked like it. How can I fix this?

Thanks for any and all help.

t.
--

Tom C., MS MA, LMHC
Private practice Psychotherapist
Bellingham, Washington, U.S.A: (360) 920-1226
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