Re: Tramp and `dired-listing-switches'

[Michael Albinus <michael.albinus@gmx.de>]

Emanuel Berg <incal@dataswamp.org> writes:

Hi Emanuel,

> I'd like one setting for `dired-listing-switches' locally on
> Debian and one remotely with Tramp, on an OpenBSD system.
>
> If I use Tramp with the Debian setting (below), and list files
> on the remote server I don't get any listing since the options
> does not compute on what is another ls(1), not GNU ls but the BSD
> (OpenBSD?) one.

The canonical way to achieve this are connection-local
variables. Unfortunately, dired does not support them (shell we extend
this?). Therefore, the Tramp manual describes an alternative:

--8<---------------cut here---------------start------------->8---
   • Remote host does not understand default options for directory
     listing

     Emacs computes the ‘dired’ options based on the local host but if
     the remote host cannot understand the same ‘ls’ command, then set
     them with a hook as follows:

          (add-hook
           'dired-before-readin-hook
           (lambda ()
             (when (file-remote-p default-directory)
               (setq dired-actual-switches "-al"))))
--8<---------------cut here---------------end--------------->8---

You might extend the lambda to check for the host name in
default-directory, and apply this only for matching hosts. Something
like

--8<---------------cut here---------------start------------->8---
(when (string-equal (file-remote-p default-directory 'host) "machine.example")
--8<---------------cut here---------------end--------------->8---

Best regards, Michael.