Re: Rhythmbox Predictive Playback - Weekly Report

[Tobias Mueller <Muelli Auftrags-Killer org>]

Hey Charlotte :)

On 28.06.2008 18:04 Charlotte Curtis wrote:
> Next Tuesday is a holiday for me (Canada Day), and some lucky folks
> get the Monday off as well, so I'm going to be heading out of internet
> range for a few days to enjoy the start of summer.
Yay! Have fun :)

> Last week was a learning experience for me: convincing Python to
> launch executables without causing the entire Rhythmbox GUI to lock
> up.
Hm. Do you know what the problems caused? Is it that Python blocked 
until the execution of the called programm finished?
How did you try it?

> I tried a number of things - threads caused problems because I
> was launching the program from a loop and I ended up with hundreds of
> little spawned processes, whereas I only wanted one to go at a time.
yeah, threading sucks :P But still, couldn't you use kind of a counter 
to check whether you've already called the program? (Yeah, thread 
safety... I know)

If you didn't try the subprocess module[1] already, give it a try!

#!/usr/bin/env python

import time
import subprocess

def dostuff(foo):
    print "Doing Stuff (%s)"%foo
    time.sleep(5)
    print foo

def execdontblock(program):
    p = subprocess.Popen(program, stdout=subprocess.PIPE)
    return p

if __name__=="__main__":
    dostuff("foo")
    p = execdontblock(['sleep','7'])
    dostuff("bar")
    print "Program %s exited" % (p.poll()==None and "has not" or "has")
    dostuff("baz")
    print "Program %s exited" % (p.poll()==None and "has not" or "has")


HTH,
  Tobi (who likes python a bit :) )

[1] http://docs.python.org/lib/module-subprocess.html