bug#70901: 30.0.50; Tramp doesn't use ControlMaster even with (setq tramp-use-connection-share nil)

[Michael Albinus via "Bug reports for GNU Emacs, the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>]

Dmitry Gutov <dmitry@gutov.dev> writes:

Hi Dmitry,

> I have ~/.ssh/config set up correctly enough that
>
> ssh <user>@<host> in the terminal connects quickly (and when I Ctrl-D
> out of it, it finishes with "Shared connection to <...> closed.")
>
> But I haven't been able to make Tramp reuse the connection.
>
> I (setq tramp-use-connection-share nil) - so it would pick up the user
> settings from my ssh config - and the first 'C-x C-f /ssh:user@host:'
> takes a lot of time anyway with its "Opening connection ...".

Are you sure you have a recent Tramp? Perhaps you use Tramp from GNU
ELPA?

tramp-use-connection-share can have three different values, t, nil or
`suppress'. And in case it is nil, nothing wrt ControlMaster will be
added to the ssh call.

Could you pls set tramp-verbose to 6, rerun your test, and show the
Tramp debug buffer?

> On a related note, are asynchronous processes supposed to use
> ControlMaster when it's available? I get "Opening connection ..." for
> every M-& call, for example.

Yes, it should do the same wrt ControlMaster.

Best regards, Michael.