Re: GUI vs TTY when saving & restoring framesets

[Stefan Monnier <monnier@iro.umontreal.ca>]

> It wasn't the intention.  OTOH, as a -nw session on GNU/Linux can have both
> GUI and tty frames, I'm not sure it is a bug, just we're entering
> unspecified territory.  I mean, what if the user creates a GUI frame from a
> -nw session, and then exits and reenters Emacs in -nw mode.  Shouldn't the
> GUI frame be restored too? We haven't decided (likely because the issue
> didn't present itself earlier than that bug report) how to deal when
> running mixed frames' instances.

I think this is basically the same issue as "multiple X11 servers".
IOW, the issue is how to handle frames on multiple "terminals" (in the
sense of `frame-terminal`).

I believe most users use Emacs in "single terminal" mode with very few
exceptions, and even when they occasionally or often use a single Emacs
session with frames on several terminals, they most likely don't want
the "desktop save&restore" to pay attention to the frames on the
"non-main terminal" because at startup those other terminals often don't
exist or aren't accessible.

There's also an issue of naming: the "main terminal" doesn't need to
have a name (and in 99% of the cases shouldn't have a name: if I save an
Emacs session in an environment where I had DISPLAY=:5, and try to
restore it in an environment where DISPLAY=:4 it should use :4 rather
than :5 to open my frames), whereas the other ones need to be named.

> Thinking about these issues, I suddenly realized that, if we were to treat
> -nw and GUI sessions as different (frameset-wise, I mean), we could just
> save the GUI frameset and the -nw frameset as distinct entities in the
> desktop file, and just restore the one appropriate. No mixing.

Sounds like a good idea.


        Stefan