How do I find the ruby interpreter?

Question

Inside a ruby script, how do I get the path to the ruby interpreter?

Example script:

  #!/path/to/ruby
  puts `#{RUBY_INTERPRETER_PATH} -e "puts 'hi'"`
  #EOF

Where RUBY_INTERPRETER_PATH is a mythical way of finding /path/to/ruby.

This is just an example, though. I realize in this case that I could just copy /path/to/ruby into the script, but I don't want to do that. I want this to work "correctly" regardless of what the #! line says. Even if running under windows.

Ciao!

Answer 1

These days (1.9+) you can use built-in methods (which are supposed to work with Jruby, etc.) like this:

RbConfig.ruby or Gem.ruby

$ irb --simple-prompt
>> RbConfig.ruby
=> "C:/installs/Ruby193/bin/ruby.exe"
>> Gem.ruby
=> "C:/installs/Ruby193/bin/ruby.exe"