Re: How to setup default program to launch directory?

[Michael Heerdegen]

Jean Louis <bugs@gnu.support> writes:

> I would like to launch programs on directories, is there any way to
> set it up by default? This is also useful to launch videos on
> directory. 

In each entry (REGEXP COMMAND...) in `dired-guess-shell-alist-user',
COMMAND

| can either be a string or a Lisp expression that evaluates to a
| string.  If this expression needs to consult the name of the file for
| which the shell commands are being requested, it can access that file
| name as the variable `file'.

(quoting from the docstring).  This is what you want to use.  Use a
catchall REGEXP and make COMMAND an expression that returns something
for directories, and nil else.  AFAICT COMMAND is also allowed to return
a list of strings.

I made it so that the expression also looks inside the directory, and
when it's full of images or media files, I return appropriate viewers.

Michael.