Non-blocking gevent stdin read

echo.py

#!/usr/bin/env python

from gevent import monkey
monkey.patch_all()
monkey.patch_sys(stdin=True, stdout=False, stderr=False)
import gevent
from gevent.queue import Queue
import sys
import signal


q = Queue()


def producer():
    while True:
        line = sys.stdin.readline()
        q.put(line)


def consumer():
    while True:
        val = q.get(True)
        print "From consumer: %s" % val


def main():
    gevent.signal(signal.SIGQUIT, gevent.kill)

    greenlets = [
        gevent.spawn(producer),
        gevent.spawn(consumer)
    ]

    try:
        gevent.joinall(greenlets)
    except KeyboardInterrupt:
        print "Exiting..."


if __name__ == '__main__':
    main()

there maybe a bug, when I use echo 123 | python echo.py,It run never end