ielm uses the cat program

ielm uses the cat program

[Alex Schroeder]

ielm.el contains the following:

  ;; A dummy process to keep comint happy. It will never get any input
  (if (comint-check-proc (current-buffer)) nil
    (start-process "ielm" (current-buffer) "cat")

When I just installed Emacs 21 on a friend's windows machine without
any unix-like tools on it, M-x ielm would not work because he did not
have cat installed.  Can we replace the cat program with anything
else?

Alex.








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In GNU Emacs 21.2.1 (i386-msvc-nt5.1.2600)
 of 2002-03-19 on buffy
configured using `configure --with-msvc (12.00)'
Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: nil
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: DES
  locale-coding-system: iso-latin-1
  default-enable-multibyte-characters: t

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Re: ielm uses the cat program

[Juanma Barranquero]

On 30 Jan 2003 13:19:07 +0100, Alex Schroeder <a.schroeder@bsiag.com> wrote:

> ielm.el contains the following:
> 
>   ;; A dummy process to keep comint happy. It will never get any input
>   (if (comint-check-proc (current-buffer)) nil
>     (start-process "ielm" (current-buffer) "cat")
> 
> When I just installed Emacs 21 on a friend's windows machine without
> any unix-like tools on it, M-x ielm would not work because he did not
> have cat installed.  Can we replace the cat program with anything
> else?

On the trunk it's already fixed:

  ;; A dummy process to keep comint happy. It will never get any input
  (unless (comint-check-proc (current-buffer))
    ;; Was cat, but on non-Unix platforms that might not exist, so
    ;; use hexl instead, which is part of the Emacs distribution.
    (condition-case nil
	(start-process "ielm" (current-buffer) "hexl")
      (file-error (start-process "ielm" (current-buffer) "cat")))
    (process-kill-without-query (ielm-process))
    (goto-char (point-max))
    

I'd suggest doing the same for EMACS_21_1_RC.

                                                           /L/e/k/t/u

Re: ielm uses the cat program

[Kevin Rodgers]

Juanma Barranquero wrote:

> On the trunk it's already fixed:
> 
>   ;; A dummy process to keep comint happy. It will never get any input
>   (unless (comint-check-proc (current-buffer))
>     ;; Was cat, but on non-Unix platforms that might not exist, so
>     ;; use hexl instead, which is part of the Emacs distribution.
>     (condition-case nil
> 	(start-process "ielm" (current-buffer) "hexl")
>       (file-error (start-process "ielm" (current-buffer) "cat")))
>     (process-kill-without-query (ielm-process))
>     (goto-char (point-max))


If hexl is distributed with Emacs, how could start-process signal a file-error?

And if it doess, why is cat considered a viable fallback?

-- 
<a href="mailto:&lt;kevin.rodgers&#64;ihs.com&gt;">Kevin Rodgers</a>

Re: ielm uses the cat program

[Juanma Barranquero]

On Thu, 30 Jan 2003 12:25:20 -0700
Kevin Rodgers <kevin.rodgers@ihs.com> wrote:

> If hexl is distributed with Emacs, how could start-process signal a file-error?

The user could delete hexl, if he doesn't use hexl-mode and doesn't want
to have the binary 'round. It's a long shot, but it is certainly posible.
Also, it could have failed building for some reason or other.

> And if it doess, why is cat considered a viable fallback?

I don't know, I didn't write the code, but I suppose the reasoning is
that one or the other are very likely to be around... and if they don't,
well, you'll get an error anyway.

-- 
Juanma Barranquero <lektu@terra.es>