Stdin pipe wrapper

procport.py

#!/usr/bin/env python
import sys
import time
import os
import resource
import subprocess


def spawn(proc):
    kw = {
            'stdin': subprocess.PIPE,
            'stdout': open('stdout.log', 'a+'),
            'stderr': open('stderr.log', 'a+')
            }
    return subprocess.Popen(proc.split(), **kw)


def touch_stdin(stdin_f):
    if not os.path.exists(stdin_f):
        open(stdin_f, "w+").close()
    return stdin_f


def wait_for_stdin(p, stdin_f):
    f = open(stdin_f, "r")
    while p.returncode is None:
        time.sleep(0.1)
        l = f.readline()
        if l.strip():
            p.stdin.write("%s" % l)
            p.stdin.flush()
        p.poll()
    f.close()
    return p.returncode


if __name__ == '__main__':
    try:
        assert len(sys.argv) == 3, \
            'Usage: %s "command" stdin_file' % sys.argv[0]
        (p, f) = sys.argv[1:]
        ec = wait_for_stdin(spawn(p), touch_stdin(f))
        assert ec == 0, \
            'Abnormal termination - exit code: %d' % ec
    except Exception, e:
        print str(e)