bidirectional tee

tee.py

#!/usr/bin/python

import sys
import subprocess
import threading
import signal
import logging

if len(sys.argv) < 3:
    sys.stderr.write("Usage: {0} output_file command [arg [arg] ...]\n"\
                        .format(sys.argv[0]))
    sys.exit(1)

name = sys.argv[0]
filename = sys.argv[1]
command = sys.argv[2:]

logging.basicConfig(
    format='%(asctime)s %(message)s',
    level=logging.INFO,
    datefmt='%Y-%m-%d %H:%M:%S',
    filename=filename,
)

p = subprocess.Popen(command, stdin=subprocess.PIPE, stdout=subprocess.PIPE,
                     stderr=subprocess.PIPE, bufsize=1)

logging.info("{0} -- started {1}".format(p.pid, repr(command)))

def t(pfrom, pto, name):
    while True:
        line = pfrom.readline()
        if not line:
            break

        pto.write(line)
        pto.flush()
        logging.info(str(p.pid) + " " + name + " " + line.rstrip('\n'))

    if pto == p.stdin:
        pto.close()

def s(*args):
    logging.info("{0} -- SIGINT".format(p.pid))
    p.send_signal(signal.SIGINT)

signal.signal(signal.SIGINT, s)

thr_in = threading.Thread(target=t, args=(sys.stdin, p.stdin, ">>"))
thr_out = threading.Thread(target=t, args=(p.stdout, sys.stdout, "<<"))
thr_err = threading.Thread(target=t, args=(p.stderr, sys.stderr, "!!"))

thr_in.daemon = True
thr_in.start()
thr_out.start()
thr_err.start()

r = p.wait()

thr_out.join()
thr_err.join()

logging.info("{0} -- exited: {1}".format(p.pid, r))

sys.exit(r)