wait_redis_server_fail.py

import subprocess
import sys 
import time

p = subprocess.Popen(
    ('redis-server', '--port', '6379', '--bind', '127.0.0.1'),
    stdout=subprocess.PIPE,
    stderr=subprocess.PIPE)

WAIT = 0.001

for i in xrange(100):
    if p.poll() is not None:
        print WAIT * i 
        sys.exit(0)
    time.sleep(WAIT)