Re: How to use groups from the command line (or at all)?

[Neal Fultz]

Also just found out that group does not work with -Q in 4.09

$ screen -S test -Q group
group command cannot be queried.

but that would be reasonably straightforward if you wanted to patch it
in - see also

https://github.com/gnu-mirror-unofficial/screen/commit/929be520ad026011ac98420f4a56fa93dff06899


On Tue, May 30, 2023 at 7:04 PM Neal Fultz <nfultz@gmail.com> wrote:
>
> Once you have started a screen session, and then made a group inside
> it, it will put you in the groups "windowlist" (C-A ") - at that point
> you can start new shells the normal way (C-A c). To switch out of the
> group to the default one, either switch by number to a shell, or go
> into the windowlist and hit backspace.
>
> I would describe this feature as more of a UI navigation tweak so that
> you don't have 30 shells in your status bar. I wouldn't  be surprised
> if it's not fully implemented for scripting externally via the -X
> flag. You might (or might not) have more luck using the :source <file>
> command. Another idea would be to pass in data via environment
> variables.
>
> HTH
>
>
>
>
> On Tue, May 30, 2023 at 10:18 AM Tim Landscheidt <tim@tim-landscheidt.de> 
> wrote:
> >
> > Hi,
> >
> > background: I use Screen 4.09.00 to control Emacs either in
> > a local GUI terminal or an SSH client from my phone by using
> > a command à la:
> >
> > | screen -dRS emacs_gnus sh -c 'pidof emacs || emacs -nw -f gnus'
> >
> > I want to customize Emacs's browse-url et al. so that they
> > do the Right Thing™ depending on which device I'm controll-
> > ing Emacs from.  My current game plan is to enhance the com-
> > mand above so that prior to executing Screen, it notes the
> > controlling device in some file /var/run/user/…  that I can
> > then read in Emacs and act upon its contents.  But it would
> > be more appropriate and better reusable code to consider
> > this information a "property" of the Screen session.  Look-
> > ing at the Screen manual, at first I thought I might store
> > the information in a register, but groups ("local", "de-
> > vice1", "device2", etc.) appear to be more fitting.
> >
> > So I launch a test session:
> >
> > | $ screen -dRS test
> >
> > and, in another terminal, I try to assign the session to a
> > group and (unsuccessfully) query its name:
> >
> > | $ screen -S test -X group local
> > | $ screen -S test -X group
> > | $
> >
> > Rereading the manual, I note that it says: "Once a new group
> > is created, it will act as a container for windows and even
> > other groups."  So I assume that I need to create the group
> > before using it:
> >
> > | $ screen -S test -X screen -t local //group
> > | $
> >
> > This causes the "test" session to show a screen with the
> > title "Group: local" and leaves me without a clue how to re-
> > turn to my shell prompt.  But even though it did something,
> > it did not succeed to assign the session to something query-
> > able from the command line:
> >
> > | $ screen -S test -X group local
> > | $ screen -S test -X group
> > | $ screen -S test -ls
> > | There is a screen on:
> > |         64047.test      (Attached)
> > | 1 Socket in /run/screen/S-tim.
> > | $
> >
> > So (how) can I create a group, assign a session to it, and
> > query the group a session is assigned to?
> >
> > TIA,
> > Tim
> >