> When I execute a ruby script by the following:
>
> ruby <path>helloworld.rb onlyarg
>
> How can I find what <path> equals?

$0 will give you the full string... then use chop it up using dirname to 
get the directory...

% cat foo.rb
puts File.dirname($0)
% ruby /Users/philip/foo.rb
/Users/philip

>
> For example, in Windows, ruby C:\scripts\helloworld.rb onlyarg
>
> helloworld.rb:
> ----------------------------------------------
> # What can I put here to display the value C:\scripts\ or C:\scripts?
> puts ARGV[0]
> ----------------------------------------------
>
> output:
> ----------------------------------------------
> onlyarg
> ----------------------------------------------
>
>
> Thanks!
>
> Matthew
>
>