Function which: 1) runs the command 2) for the specified time (duration) and 3) pipes output to the file AND to screen (live).

python+tee.py

import time
from time import strftime
import subprocess


def runForDuration(cmdline, duration, logFile):
    teeCommand = ['tee',  '-a', logFile ] # quick and dirty hack to get log to file
    try:
        p1 = subprocess.Popen(cmdline, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
        p2 = subprocess.Popen(teeCommand, stdin=p1.stdout)
        time.sleep(duration)
        p1.terminate()
    except OSError as e:
        print "✖ OS Error during command: " + " ".join(cmdline)
        print "✖ OS Error: " + e.strerror

runForDuration(['ping', 'github.com'], 10, "logfile.txt")