subprocess pipe question

Rita rmorgan466 at
Tue Feb 22 18:44:20 EST 2011

I have a process like this,

def run(cmd):
  #cmd=a process which writes a lot of data. Binary/ASCII data

I would like to get cmd's return code so I am doing this,

def run(cmd):
  print rc # and I get 'None' regardless of what cmd gives me (0 thru 255
are valid return codes)
  return p.stdout

When using wait() it works a bit better but not consistent
def run(cmd):
  print rc
  return p.stdout

When the output of cmd is a small ascii file it works perfectly fine, but
when the file is large (more than 2MB) the process just waits for ever (I am
guessing its blocking?).  When I use the communicate call it works perfectly
but my process is consuming way too much memory.

Is there a better way to get my return code consistently efficiently and not
take up so much memory?

--- Get your facts first, then you can distort them as you please.--
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <>

More information about the Python-list mailing list