Re: How to communicate with a running external process with

[Thorsten Jolitz <tjolitz@gmail.com>]

"Pascal J. Bourguignon" <pjb@informatimago.com> writes:

> Thorsten Jolitz <tjolitz@gmail.com> writes:
>
>> OTOH, this topic has become quite interesting, and I'm still curious
>> about my original question: how to use all these UNP mechanisms from
>> Emacs Lisp when the other (Lisp) process is not a subprocess but already
>> running (with a given PID). 
>
> You started specifying only another "process" PID, but now you're saying
> it's a "Lisp" process.  What does that mean?

[...]

> But you are not saying what the program of the other process is. 

[...]

Not really, this is the very beginning of my original post:

,----------------------------------------------------------------------------
| From: Thorsten Jolitz <tjolitz@gmail.com>
| Subject: How to communicate with a running external process with given PID?
| Newsgroups: gmane.emacs.help
| To: help-gnu-emacs@gnu.org
| Date: Sat, 20 Jul 2013 11:06:55 +0200 (3 days, 10 hours, 55 minutes ago)
| 
| 
| Hi List, 
| 
| say I want to call another program (more exactly, another Lisp program
| that is not Emacs Lisp) from an Emacs Lisp program. 
`----------------------------------------------------------------------------

> Now, you said lisp, but since you're building a history of imprecise
> language, perhaps we should assume you mean Common Lisp?

That wasn't my intention, I was just interested in the Emacs Lisp side
when starting the thread and thought the exact Lisp dialect of the other
side is irrelevant (its an uncommon lisp). After rereading that UNP
stuff I'm aware that the other side is important too.

> There's a protocol that has been defined specifically to communicate
> between an emacs and a Common Lisp process, with which a whole IDE has
> been built in emacs, named slime (the backend, the library that
> implements that protocol on the Common Lisp side is called swank (as is
> called the protocol)).  With slime/swank you can connect a CL process
> with an emacs, and from emacs, send CL expressions to evaluate to the CL
> process and receive back results, and debug and develop CL programs.
> But if you specifically meant that, you could easily read the manual of
> slime which indicates how to create from emacs a new CL inferior process
> running swank, and how to connect from emacs to an existing CL process
> that runs a SWANK server (therefore that is listening to a specific
> port, just like a HTTP server).

I did not mean Common Lisp, but there is a Swank implementation for my
Uncommon Lisp of interest, and it did not occur to me to consider it -
so thanks for this marvelous tip!

-- 
cheers,
Thorsten