Sort windows by last access time

[klayman]

There is a point at which jumpapping loses to alt-tabbing. When I work on a project I often has to switch between an editor and some pdf-documents in evince. With swift alt-tabbing I always get the most recent accessed pdf-document. When I use jumpapp evince I get the first (or, with -r option, the last) opened pdf-document. It's not so handy.

I think that it's possible to sort the list of windows returned by wmctrl -lpx by the last focus timestamp. Here is some code I googled from stackoverflow with minor edits:

XTIME="_NET_WM_USER_TIME" # a shorter name for xprop query that shoul return timestamps
export TMPDIR=/dev/shm    # save tmp files to memory to make it faster
LST=`mktemp`              # tmp file to store our listing 
wmctrl -lx |  awk -F' ' '{printf("%s\t%s    \t",$1,$3); for(i=5;i<=NF;i++) printf("%s",$i); printf("\n")  }'  > $LST # pretty-print our listing of windows into the tmp file
 # To each line of listing, prepend a timestamp acquired via an xprop call
 # Use awk to find a line whose 3rd column (winclass) matches the window class "evince.Evince" and among those that do, find the one whose timestamp is the largest
while read LINE; do ID=`echo "$LINE"|cut -f 1`; TIME=`xprop -id $ID $XTIME`;  TIME="${TIME/* = /}"; echo -e "$TIME\t$LINE" ; done <$LST | awk -v s="evince.Evince" '$3 == s {if($1>max){max=$1;line=$0};};END{print line}'
rm $LST  # delete tmp file

[mkropat]

Good idea! That should probably be the default behavior, and if not, at the very least be an option.

No promises about time frame, but I'll see if I can put something together in the next week or two.

[mkropat]

I'm still working on this btw in my free time and I want to see this happen. Might be another month or two before I get it done though :)

[klayman]

Meantime I have found a workaround - a separate python script that returns the sorted list instead of the wmctrl -lpx output:

#!/usr/bin/env python
# encoding: UTF-8
#
# This is a simple script for sorting the wmctrl -lpx output by a last focus timestamp
import subprocess

# obtaining the list of windows initially sorted by the creation timestamp
wlist = subprocess.check_output( 'wmctrl -lpx', shell = True )

wlist = wlist.splitlines()

# getting the focus timestamp by the window id
def focustime( line ):
    time = subprocess.check_output( 'xprop -id ' + line.split()[ 0 ] + ' _NET_WM_USER_TIME', shell = True )
    if len( time.split( ' = ' ) ) > 1:
        time = time.split( ' = ' )[ 1 ]
    else:
        time = '0'
    return time

# using the focus timestamp as a sorting key
wlist.sort( key = focustime )

print( "\n".join( wlist ) )

Sure, it is possible to make the same in the jumpapp script directly, but I'm not good at bash. For now I only changed the line in list_windows() to call this python script instead of wmctrl -lpx.

[mkropat]

Cool! Working code helps, even if it's in a different language.

How's the speed with that script in place? My fear was that jumpapp would feel slow if it had to spawn another process for every process line, but maybe it's not so bad.

[klayman]

I didn't test it with many windows opened, but for a list of 10 processes there may be a slight delay, I think less than 0.1 s - it's almost unnoticeable. And there is a huge usability improvement in some workflows.

[mkropat]

Do you want to help me test the beta version of this functionality? I've created a new branch for my development work: sort-by-access

If you already have the git repo cloned, you can test it with:

git fetch
git checkout sort-by-access
make && sudo make install

The code still needs a little polish, but I just wanted to get your thoughts about behavior + performance.

[klayman]

Strange, but your code does not work for me. Only for Opera browser windows I get the expected behaviour, but for sakura, mucommander and atril (evince fork) jumpapping doesn't differ from the old (master branch) behaviour.

[mkropat]

Good to know. Thanks for testing. My guess is that the window access time logic isn't working on your desktop. Two questions:

1. What window manager are you using? Maybe I can reproduce it locally
2. From the branch again, can you run jumpapp -L NAME with NAME as a program that works (like Opera) and with NAME as a program that doesn't sort correctly (like sakura)?

The first column of output should be the window last access time, so if it's 0 or some other non-valid value, that would explain why it's not working.

[klayman]

1. Currently I use openbox WM.
2. Yes, you are right. Here is the output for Opera:

393620798 0x02c000b3 localhost 31234 0 Opera: Developer Tools - https://mail.google.com/mail/u/0/ - Opera
393600258 0x02c00001 localhost 31234 0 Opera: Re: [jumpapp] Sort windows by last access time (#5) - Gmail - Opera

and for sakura:

0 0x05600007 localhost 23839 0 Sakura: ~
0 0x05000007 localhost 12021 0 Sakura: scripts

That said, xprop -id ######## _NET_WM_USER_TIME works fine for sakura and others.

[mkropat]

Think I figured it out: Openbox does not support _NET_WM_USER_TIME_WINDOW. Jumpapp needs to check _NET_WM_USER_TIME_WINDOW first, however, otherwise it won't work on Cinnamon (the window manager I use). As a workaround in case the _NET_WM_USER_TIME_WINDOW value is a lie (as seems to be the case in Openbox), Jumpapp will now fall back to trying _NET_WM_USER_TIME on the original window.

Do you mind testing out the latest code? If you still have it checked out you can do:

git pull --ff-only
make && sudo make install

[klayman]

It works, thank you!

[mkropat]

Cool, I need to clean up the code then I'll put together a new release with this change.

If people complain about it being noticeably slower, I may have to make the new sorting optional, but I only plan to do that if people actually give feedback about it.

[ghost]

Have you done it? It's not working for me..

[mkropat]

Unfortunately, no. I only implemented a prototype. It would be really useful though, so give me a few weeks and I'll see if I can get the latest changes merged into the prototype, and add unit tests.

[markolenik]

Thanks for the enhancement, works in gnome!

[mkropat]

This feature just got released with the good work done in #13 and #14. Try it out and feel free to open a new issue if you find problems.