shell-command-sentinel hook?

shell-command-sentinel hook?

[Christopher Howard]

Hi, I was just wondering if it would be difficult/problematic to patch simple.el to provide some kind of hook so that, when async shell commands complete, users can run arbitrary elisp? I imagine this would get inserted at the end of shell-command-sentinel...?

I've been getting in the habit lately of moving my activities out of Gnome console and instead running shell commands with async-shell-command. But something I miss is that Gnome console will send a notification at the end of the command which is very visible on the desktop. This can be reproduced in Emacs by adding " && notify-send \"some message\"" onto the end of the command. This works, and could be wrapped in various ways, but it would be nice if the exit code was passed on as well to the callback. I imagine other people would come up with various other creative uses of the hook, especially if we also passed in the command string to the callback.

Am running GNU Emacs 29.1.

-- 
📛 Christopher Howard
🚀 gemini://gem.librehacker.com
🌐 http://gem.librehacker.com

בראשית ברא אלהים את השמים ואת הארץ

Re: shell-command-sentinel hook?

[Eli Zaretskii]

> Date: Mon, 4 Mar 2024 09:00:11 -0900
> From: Christopher Howard <christopher@librehacker.com>
> 
> Hi, I was just wondering if it would be difficult/problematic to patch simple.el to provide some kind of hook so that, when async shell commands complete, users can run arbitrary elisp? I imagine this would get inserted at the end of shell-command-sentinel...?

Why cannot you simply override shell-command-sentinel with your own
function?

Re: shell-command-sentinel hook?

[Christopher Howard]

On Mon, Mar 04, 2024 at 10:08:12PM +0200, Eli Zaretskii wrote:
> Why cannot you simply override shell-command-sentinel with your own
> function?

Hi, I think I might end up doing that on my install. But, as an emacs-devel proposal, I thought it would be more useful in-general to have it available in an actual hook. (Hooks are great!) Since I cannot simply wrap shell-command-sentinel (it does not return the message and signal) my overide would need to reproduce the initial part of the function...

``` elisp
  (when (memq (process-status process) '(exit signal))
    (shell-command-set-point-after-cmd (process-buffer process))
    ...etc...
```

That might break in the next emacs release if you guys change any of those functions (memq, shell-command-set-point-after-cmd, etc.) or if you guys replace the sentinel with something else.

-- 
Christopher Howard

Re: shell-command-sentinel hook?

[Suhail Singh]

Christopher Howard <christopher@librehacker.com> writes:

> my overide would need to reproduce the initial part of the function...

An :after advice would obviate that, unless I'm mistaken.  Not to imply
that a hook may not still be helpful, but IIUC the code duplication
isn't necessary.

-- 
Suhail

Re: shell-command-sentinel hook?

[Christopher Howard]

Okay, thank you. I already implemented the override function, following the previous advice, but that sounds like a good idea as well.

{http://gem.librehacker.com/gemlog/starlog/20240304-0.gmi}

On Tue, Mar 05, 2024 at 11:30:28PM -0500, Suhail Singh wrote:
> An :after advice would obviate that, unless I'm mistaken.  Not to imply
> that a hook may not still be helpful, but IIUC the code duplication
> isn't necessary.

-- 
Christopher Howard