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rubymacosunixterminal

Launching Ruby without the prefix "Ruby"

I'm on OS X (with bash) and a newbie at unix. I want to know if it's possible to amend some file such that to run a ruby program, I don't need "ruby file.rb", but instead can just run "ruby.rb".

Is there a reason NOT to do this?

Thanks!

Solution

  • Yes you can do this.

    Assuming ruby.rb has something like this in it:

    #!/usr/bin/env ruby
puts 'Hello world'

    At the command line: chmod +x ruby.rb

    This makes it executable.

    Then you can execute it like this:

    ./ruby.rb

    EDIT (Jörg W Mittag): Using #!/usr/bin/env ruby instead of #!/usr/bin/ruby as the shebang line is more portable, because on every Unix produced in the last 20 years, the env command is known to live in /usr/bin, whereas Ruby installations are typically all over the place. (E.g., mine lives in /home/joerg/jruby-1.2.0/bin/ruby.)