module EnvUtil def rubybin unless ENV["RUBYOPT"] end if ruby = ENV["RUBY"] return ruby end ruby = "ruby" rubyexe = ruby+".exe" 3.times do if File.exist? ruby and File.executable? ruby and !File.directory? ruby return File.expand_path(ruby) end if File.exist? rubyexe and File.executable? rubyexe return File.expand_path(ruby) end ruby = File.join("..", ruby) end begin require "rbconfig" File.join( Config::CONFIG["bindir"], Config::CONFIG["ruby_install_name"] + Config::CONFIG["EXEEXT"] ) rescue LoadError "ruby" end end module_function :rubybin end