Re: suggested feature -- console-mode frame title sets Xterm title

[Martin Pool <mbp@sourcefrog.net>]

On 14 Oct 2003, Eli Zaretskii <eliz@elta.co.il> wrote:
> > Date: Tue, 14 Oct 2003 13:59:33 +1000
> > From: Martin Pool <mbp@sourcefrog.net>
> > 
> > I'd guess the number of people using multiple frames on a text
> > terminal is fairly small, though non-zero.
> 
> I do.

Thanks for responding!

> Please note that some Emacs features, such as Speedbar, create their
> own dedicated frames, so if you use those features, you'll be using
> multiple frames on text-mode displays whether you want that or not.
> 
> > I would also guess that
> > more than half the people using emacs in termcap mode are doing so
> > from some kind of terminal emulator under a window system (xterm,
> > putty, etc) and so could benefit from seeing the title.
> 
> Sorry, I don't see how the latter follows from the former.  Could you
> please explain?

With this feature added, people gain control over a part of their
environment (the xterm titlebar) that previously showed a fixed and
possibly unhelpful string.  The patch puts more of the environment
under the user's control (through mode-line-format), and I think that
control is useful in itself.

One way it might be helpful is in distinguishing emacs xterms from
each other or from other xterms.  I was motivated to do this by having
several emacs sessions open on different machines over ssh.

If you do happen to have several tty frames open, labelling them in
the title bar might help keep track of which one is which.

Some people like to have information in the title bar that won't fit
in their modeline.

Also, vim does it :-)

> > If I had to decide, I would probably just remove the 'F%d' behaviour.
> > (Specifically, remove that indicator from the toolbar, and remove it
> > as the default name for tty frames.)  This is a bit disturbing to
> > people who were accustomed to those features, but it does not really
> > remove any functionality, as they can still name frames by hand and
> > switch between them.
> 
> I think it'd be annoying to force the user to set frame names
> manually.  That is why I kept the old F1 name and generalized it to
> Fn back when I made multiple frames work on ttys.
> 
> How about if we have an option that would cause Emacs to either use
> the F<num> names (default) or the new names you implemented.  If it
> uses F<num>, that name will be displayed on the mode line, as today;
> otherwise, the name will be displayed in the xterm's title and be
> removed from the mode line.

OK.

Should this be a separate variable, or just controlled by
tty-frame-use-title?  Should it be on by default?

> (I also think that the code that sets the xterm's title should test
> whether the required capability is supported, in case we run on
> something that is not an xterm at all.)

The logic is that it is turned on if you set tty-frame-use-title (t by
default) and if emacs knows how to set it.  emacs knows how to set it
if the escape sequences are set either in termcap, or in
tty-frame-title-start/end, typically by xterm.el.  So on e.g. a text
mode virtual console with no title, it should just do nothing.

-- 
Martin