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 \'h         


        

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"

Answer 2

To get the path of the currently running ruby interpreter:

require 'rbconfig'
RUBY_INTERPRETER_PATH = File.join(RbConfig::CONFIG["bindir"],
                                  RbConfig::CONFIG["RUBY_INSTALL_NAME"] +
                                  RbConfig::CONFIG["EXEEXT"])