zombie debootstrap

import subprocess
import fcntl
import sys
import os
import select

def set_nonblock(f):
    flags = fcntl.fcntl(f, fcntl.F_GETFL)
    fcntl.fcntl(f, fcntl.F_SETFL, flags | os.O_NONBLOCK)

def handle(f, name):
    data = f.read()
    sys.stderr.write("read %s: %s\n" % (name, repr(data)))
    if data == "":
        f.close()

args = ['/usr/sbin/debootstrap', '--arch=i386', 'trusty', '/tmp/tmpBQAxhc', 'http://archive.ubuntu.com/ubuntu']
stdin_arg = file('/dev/null', 'r')
proc = subprocess.Popen(args, stdin=stdin_arg, stderr=subprocess.PIPE, stdout=subprocess.PIPE)
set_nonblock(proc.stdout)
set_nonblock(proc.stderr)

while True:
    fds = []
    if not proc.stdout.closed:
        fds.append(proc.stdout)
    if not proc.stderr.closed:
        fds.append(proc.stderr)
    if not fds:
        break
    ready = select.select(fds, [], [])[0]
    if proc.stdout in ready:
        handle(proc.stdout, "stdout")
    if proc.stderr in ready:
        handle(proc.stderr, "stderr")