From mboxrd@z Thu Jan 1 00:00:00 1970 From: John Kitchin Subject: Re: long running processes Date: Thu, 19 Nov 2015 08:38:07 -0500 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain Return-path: Received: from eggs.gnu.org ([2001:4830:134:3::10]:35406) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZzPPg-0000g1-Mz for emacs-orgmode@gnu.org; Thu, 19 Nov 2015 08:38:13 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZzPPd-0005dh-Cd for emacs-orgmode@gnu.org; Thu, 19 Nov 2015 08:38:12 -0500 Received: from mail-qg0-x22b.google.com ([2607:f8b0:400d:c04::22b]:34730) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZzPPd-0005dd-7V for emacs-orgmode@gnu.org; Thu, 19 Nov 2015 08:38:09 -0500 Received: by qgeb1 with SMTP id b1so50771078qge.1 for ; Thu, 19 Nov 2015 05:38:08 -0800 (PST) In-reply-to: List-Id: "General discussions about Org-mode." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-orgmode-bounces+geo-emacs-orgmode=m.gmane.org@gnu.org Sender: emacs-orgmode-bounces+geo-emacs-orgmode=m.gmane.org@gnu.org To: Tom Cc: emacs-orgmode@gnu.org Your suggestions sounds possible to me. If you are up for it, I suggest trying to implement it, and offering it as a patch. Tom writes: > On Wed, Nov 18, 2015 at 2:55 PM, John Kitchin > wrote: > >> I am pretty sure this is not directly possible right now. >> >> Some approaches that resemble it could be: >> 1. write a src block that will be tangled to a script. >> 2. tangle the block >> 3. Run the script in a shell src block with an & so it runs >> non-blocking. >> >> or, use an elisp block like: >> >> (org-babel-tangle) >> (async-shell-command "your script" some-output-buffer) >> >> I don't know a way to get continuous updated output in an org-buffer >> though. >> > > Thanks for the response. I didn't necessarily expect continuous output into > the org-buffer itself to work, but I don't see why the Python subprocess > can't display output as it occurs. After all, it uses comint, and comint > certainly has facilities for collecting output incrementally while still > displaying it (cf comint-output-filter-functions). > > It looks to me like the problem is that org-babel-comint-with-output uses a > "while" loop to collect process output (ob-comint.el:92). At least, it > could insert the output into the subprocess buffer and make redisplay > happen. > > But I'm not sure why the code is written that way anyway. Long running > "while" loops in Emacs code don't seem like a good idea to begin with. > Wouldn't the more natural way for this code to be written in Emacs be the > following? > > - an output filter gets added to the subprocess that collects output > - the code is sent to the subprocess for execution > - the command returns > - the output filter inserts any data it gets into the subprocess buffer, > into its "results" data structure, perhaps even into the org-buffer > - when the output filter gets the eoe-indicator, it removes itself from the > output filter list and sends a notification that execution has completed > > If the user schedules a second block for execution, the simplest thing to > do is return an error if there is already a block executing for that > subprocess; alternatively, it could be queued somewhere. > > Thanks, > Tom -- Professor John Kitchin Doherty Hall A207F Department of Chemical Engineering Carnegie Mellon University Pittsburgh, PA 15213 412-268-7803 @johnkitchin http://kitchingroup.cheme.cmu.edu