[ruby-talk:6134] emacs-mode

My emacs-mode does not work correctly.  I did put the following in my
.emacs:
----------------------------------
(defun ruby-xmp-region (reg-start reg-end))

(autoload 'ruby-mode "ruby-mode"
  "Mode for editing ruby source files")
(setq auto-mode-alist
      (append '(("\\.rb$" . ruby-mode)) auto-mode-alist))
(setq interpreter-mode-alist (append '(("^#!.*ruby" . ruby-mode))
                                     interpreter-mode-alist))
    
;;; (2) set to road inf-ruby and set inf-ruby key definition in ruby-mode.
;;;
(autoload 'run-ruby "inf-ruby"
  "Run an inferior Ruby process")
(autoload 'inf-ruby-keys "inf-ruby"
  "Set local key defs for inf-ruby in ruby-mode")
(add-hook 'ruby-mode-hook
          '(lambda ()
             (inf-ruby-keys)
             ))
 
(setq ruby-indent-level 4)
--------------------------------------
I get syntax highlighting while working in X11 but the following keys
does not work 

C-c C-s         run-ruby

Error message: "Searching for program: no such file or directory, irb"


C-c C-z         switch-to-ruby

Comment: This causes emacs to exit to a background process - the same
as C-z.
----------------------------------------------------------
I do not really understand the instruction in inf-ruby.el: 

";;; (0) check ruby-program-name variable that can run your
environment."

Can somebody explain it to me please?

Johann

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