bug#72427: emacs-daemons: string handling error

[Christopher Howard]

The emacs-daemons we use, which is the melpa-stable version, is very old (about 
6 years out of date), and has a bug caused by a string handling issue. This 
occurs when "Daemons Always Sudo" is set to on, which is required if you want 
to view the system processes of shepherd, rather than your home processes.

Recipe:

1. Use "customize-group daemons" and set "Daemons Always Sudo" to "on". Save 
and set, or set for the session.
2. M-x daemons.

This will throw an error along the lines of

```
Operation on Daemons Always Sudo: 0
cd: No such directory: /sudo::/tmp/tmp.NyPiPKi1eL

```

If you look into this, you'll discover that function "daemons--sudo" does not 
trim the newline off the end of the result when it calls 
"daemons--shell-command-to-string". A slightly modified version like so will 
work (the same, but with string-trim inserted):

```
(with-eval-after-load 'daemons
  (defun daemons--sudo ()
    "Become root using TRAMP (if on local system).

Switches to a temporary directory to minimise damage potential.

Note that this only works on the local system, not remote systems.  For a remote
system you need to specify your own TRAMP path with a privileged user.

e.g. /ssh:me@example.com|sudo:example.com:"
    (unless (daemons--using-tramp-path-p default-directory)
      (let ((tempdir (string-trim (daemons--shell-command-to-string "mktemp 
-d"))))
        (cd (format "/sudo::%s" tempdir))))))
```

I wanted to reach out to the author/maintainer and find out if he was planning 
to tag another release for melpa-stable, but I don't have a github account and 
don't allow github javascript. I was unable to find any other contact 
information for him. Maybe somebody who uses github would want to reach out to 
him. Or if not, maybe we would want to patch the stable version.

Here is my system information:

```
christopher@theoden 
------------------- 
OS: Guix System x86_64 
Host: OptiPlex 9020 00 
Kernel: 5.15.161-gnu 
Uptime: 29 days, 22 hours, 33 mins 
Packages: 167 (guix-system), 251 (guix-user) 
Shell: bash 5.1.16 
Resolution: 1920x1080 
DE: GNOME 
Theme: Adwaita [GTK2/3] 
Icons: Adwaita [GTK2/3] 
Terminal: shepherd 
CPU: Intel i5-4570 (4) @ 3.600GHz 
GPU: AMD ATI Radeon HD 8490 / R5 235X OEM 
GPU: Intel HD Graphics 
Memory: 4265MiB / 15914MiB 
```

``` guix describe
Generation 137  Jul 27 2024 05:04:20    (current)
  guix c6ff1d6
    repository URL: https://git.savannah.gnu.org/git/guix.git
    branch: master
    commit: c6ff1d6ff761af0bd9bac5403fd834f04a14a192
```

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

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