[emacs-berlin] Tramp mode with custom location for SSH config

[Michael Albinus]

jman <emacs-berlin at city17.xyz> writes:

Hi,

> It works great! For the record, I have added the following
> snippet to my Emacs config:
>
> (add-to-list 'tramp-methods
>              '("ssh-j" ;; LOL slight variation for the "ssh" method
>                (tramp-login-program "ssh")
>                (tramp-login-args
>                 (("-F" "$XDG_CONFIG_HOME/ssh/config")
>                  ("-l" "%u")
>                  ("-p" "%p")
>                  ("%c")
>                  ("-e" "none")
>                  ("%h")))
>                (tramp-async-args
>                 (("-q")))
>                (tramp-direct-async t)
>                (tramp-remote-shell "/bin/sh")
>                (tramp-remote-shell-login
>                 ("-l"))
>                (tramp-remote-shell-args
>                 ("-c"))))
>
>
> Just one minor wrinkle since I am not great lisper. For the additional
> "-F" parameter I wanted to use:
>
> ("-F" (concat (getenv "XDG_CONFIG_HOME") "/ssh/config"))
>
> it is successfully evaluated (C-x C-e), but then TRAMP returns this error:
>
> (wrong-type-argument "char-or-string-p (concat (getenv XDG_CONFIG_HOME) /ssh/config)"
>
> Why?

It is a quoted list, see the leading apostrophe in '(ssh ...
If you want to have it evaluated, you would need

--8<---------------cut here---------------start------------->8---
(add-to-list 'tramp-methods
             `("ssh-j" ;; LOL slight variation for the "ssh" method
               (tramp-login-program "ssh")
               (tramp-login-args
                (("-F" ,(concat (getenv "XDG_CONFIG_HOME") "/ssh/config"))
               ...
--8<---------------cut here---------------end--------------->8---

Best regards, Michael.