Re: Some developement questions

[hw <hw@adminart.net>]

Eli Zaretskii <eliz@gnu.org> writes:

>> From: hw <hw@adminart.net>
>> Cc: spacibba@aol.com,  radon.neon@gmail.com,  flexibeast@gmail.com,  emacs-devel@gnu.org
>> Date: Mon, 27 Aug 2018 00:51:38 +0200
>> 
>> >> In theory, Emacs could find out which variables are being defined in
>> >> ~/.emacs and whether they are already known or not, like by checking if
>> >> they can successfully be described.  The unknown variables could then be
>> >> brought to the attention of the user.
>> >
>> > That would definitely annoy me, for example: I have a lot of settings
>> > of "unknown" variables, in preparation for when they will become known
>> > (when the corresponding package is loaded on demand).
>> 
>> Hmm, yes, there would have to be a way to tell the check which unknown
>> variables it must not consider.  Would it bother you when there was
>> merely a function you needed to run to perform the check?  I wouldn't
>> consider it useful that the check would be done on every startup.
>
> If there were a setting to disable the check, that'd be fine by me.
> Of course, then we'd have an argument about the default of that
> setting ;-)

Why, you want a check on every startup? ;)

>> >> Unfortunately, the Emacs server can still not be used from remote
>> >> machines --- or can it finally?
>> >
>> > Yes, it can.
>> 
>> Wow!  Finally!  Awesome!  I have to see if I can get that to work right
>> now!  That would be incredibly helpful ...
>> 
>> Hm, no, it doesn't work:  It says it connects, but then it either says
>> "*ERROR*: Display :0 can't be opened" or "*ERROR*: Could not open file:
>> /dev/pts/35".
>> [...]
>> So how do I get this to work?
>
> Read about that in the manual, nodes "TCP Emacs server" and the
> description of the --tramp-prefix= option under "emacsclient Options".

I don't understand this documentation.  It's a good example for why
people turn to a search engine.  And I don't remember how to get back
when following links in info documentation --- if I ever knew that and
if there even is a way (I seem to vaguely remember that there is ...).
This documentation is really difficult to read.

Anyway, why would I need to forward the port via ssh?  Emacs can use it
just fine without, and it would be already in use.  I would expect using
a secure connection to be the default anyway.

I'm guessing the documentation wants me to allow the emacs daemon to
access /dev/pts/35 via tramp.  To be able to do that, emacs would have
to ask me for my password, which it can not do because it can not open
the terminal.  Tramp can be extremely finicky, and what are the
difficulties SELinux might put into my way when doing this?

And what file is there to access when I want an X frame?

The example in the documentation is the wrong way round: The server is
running on the remote machine.  If I wanted to run emacs locally on my
workstation, I could just do that, but I want it to run on the server
because I don't shut the server down but my workstation.


I'm running it now with Emacs as daemon on the server and 'ssh -Y
server'.  That allows me to get either X frames or to use the terminal.
I needed to restart the tmux session because this does not work with a
tmux session that was started without the -Y option of ssh.

But I'd like to use the Emacs server without such detours.  Can remote
Emacs not simply be simple?  Why doesn't the locally running emacsclient
allow the remote Emacs server to access the terminal transparently?