Re: run emacs in batch mode without a tty

[Sam Halliday]

Aha! It would appear that when emacs is started in -batch mode then the program 
exits when it runs through the initial script.

But my tests are starting up a process, attaching a sentinel and then reacting 
to some triggers in that file. Under non-batch mode, emacs stays open until I 
call `kill-emacs`... but *now* it's dying too early.

So my question then becomes: is there a way to stop emacs -batch from 
terminating when it reaches the end of the script? i.e. require an explicit 
kill-emacs call.


On Friday, 3 July 2015 21:43:27 UTC+1, Sam Halliday  wrote:
> On Friday, 3 July 2015 21:14:36 UTC+1, Eli Zaretskii  wrote:
> > > Date: Fri, 3 Jul 2015 10:07:06 -0700 (PDT)
> > > From: Sam Halliday <sam.halliday@gmail.com>
> > > 
> > > >   emacs -batch --eval "(princ \"Hello, world\!\n\")" < /dev/null > foo
> > > 
> > > Aah, the difference is that you're using `-batch`
> > 
> > Excuse me?  It was you who asked specifically about the batch mode:
> > 
> > > Is it possible to run emacs in batch mode without access to a tty? Is 
> > > there a way to mock a tty for these purposes?
> >   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> 
> I wasn't aware that there was a flag to turn emacs into a batch processor. 
> You can invoke commands and load lisp files for purely automated testing 
> without the -batch flag, and that is exactly what we are doing. I was calling 
> that batch mode, but now I don't know what to call it.
> 
> 
> > > and that does allow me to do *some* things in the docker container, but 
> > > emacs seems to just exit when I start a `process`. The docs don't mention 
> > > this as a caveat http://www.emacswiki.org/emacs/BatchMode
> > 
> > What do you mean by "start a process"?
> 
> I mean start a 
> http://www.gnu.org/software/emacs/manual/html_node/elisp/Processes.html
> 
> > > Is there anything that you can think of that might cause a -batch emacs 
> > > to exit early?
> > 
> > How do you see it exiting early?  Please provide the details of what
> > you see, as I have no way of trying this on a system similar to yours.
> 
> Well, this is literally all the information I have: the stdout
> 
> http://fommil.com/github.com/ensime/ensime-emacs/drone/ee99fc5d368cafc2dd583520f9fe8e9e23faadb6
> 
> from running this script
> 
> https://github.com/fommil/ensime-emacs/blob/drone/test/run_emacs_tests.sh
> 
> The last thing we see is the output from this function call (which starts the 
> process) 
> https://github.com/fommil/ensime-emacs/blob/drone/ensime-startup.el#L215
> 
> So I'm interested to know what implication the -batch flag has for the 
> functionality of emacs. Specifically: launching/monitoring processes, and 
> navigating buffers (i.e. spoofing user actions).
> 
> Best regards,
> Sam