On Sat, Dec 6, 2008 at 6:25 PM, Python Nutter <[EMAIL PROTECTED]> wrote: > I'm on my phone so excuse the simple reply. > From what I skimmed you are wrapping shell commands which is what I do > all the time. Some hints. 1) look into popen or subprocess in place of > execute for more flexibility. I use popen a lot and assigning a popen > call to an object name let's you parse the output and make informed > decisions depending on what the shell program outputs.
So I took a peak at subprocess.Popen --> looks like that's the direction I would be headed for parallel processes ... a real simple way to see it work for me was: p2 = subprocess.Popen(["lame","--silent","test.wav","test.mp3"]) p3 = subprocess.Popen(["lame","--silent","test2.wav","test2.mp3"]) p2.wait() p3.wait() top showed that both cores get busy and it takes half the time! So that's great -- when I tried to add the flac decoding through stdout I was able to accomplish it as well ... I was mimicing the command of "flac --decode --stdout test.flac | lame - test.mp3" ... see: p = subprocess.Popen(["flac","--decode","--stdout","test.flac"], stdout=subprocess.PIPE) p2 = subprocess.Popen(["lame","-","test.mp3"], stdin=subprocess.PIPE) p2.communicate(p.communicate()[0]) That did the trick - it worked! However, it was *very* slow! The python script has a "real" time of 2m22.504s whereas if I run it from the command line it is only 0m18.594s. Not sure why this is ... The last piece of my puzzle though, I am having trouble wrapping my head around ... I will have a list of files ["file1.flac","file2.flac","file3.flac","etc"] and I want the program to tackle compressing two at a time ... but not more than two at a time (or four, or eight, or whatever) because that's not going to help me at all (I have dual cores right now) ... I am having trouble thinking how I can create the algorithm that would do this for me ... Thanks everyone. Maybe after a good night's sleep it will come to me. If you have any ideas - would love to hear them. Damon _______________________________________________ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
