#!/usr/bin/env python
import os
import sys
from select import select
from subprocess import PIPE, Popen
 
# dummy process to generate some output with a delay
p = Popen([sys.executable, '-u', '-c', """import time
for i in range(5):
    print("%d" % i)
    time.sleep(.1)
"""], bufsize=0, stdout=PIPE)
 
# read input from the subprocess and stdin concurrently
timeout = .4 # seconds
rlist = [f.fileno() for f in [sys.stdin, p.stdout]]
while rlist: # while not EOF
    for fd in select(rlist, [], [], timeout)[0]:
        input_data = os.read(fd, 512)
        source = "stdin" if fd == sys.stdin.fileno() else "subprocess"
        print("got %r from %s" % (input_data, source))
        if not input_data: # EOF
            rlist.remove(fd)
p.stdout.close()
p.wait()

IyEvdXNyL2Jpbi9lbnYgcHl0aG9uCmltcG9ydCBvcwppbXBvcnQgc3lzCmZyb20gc2VsZWN0IGltcG9ydCBzZWxlY3QKZnJvbSBzdWJwcm9jZXNzIGltcG9ydCBQSVBFLCBQb3BlbgoKIyBkdW1teSBwcm9jZXNzIHRvIGdlbmVyYXRlIHNvbWUgb3V0cHV0IHdpdGggYSBkZWxheQpwID0gUG9wZW4oW3N5cy5leGVjdXRhYmxlLCAnLXUnLCAnLWMnLCAiIiJpbXBvcnQgdGltZQpmb3IgaSBpbiByYW5nZSg1KToKICAgIHByaW50KCIlZCIgJSBpKQogICAgdGltZS5zbGVlcCguMSkKIiIiXSwgYnVmc2l6ZT0wLCBzdGRvdXQ9UElQRSkKCiMgcmVhZCBpbnB1dCBmcm9tIHRoZSBzdWJwcm9jZXNzIGFuZCBzdGRpbiBjb25jdXJyZW50bHkKdGltZW91dCA9IC40ICMgc2Vjb25kcwpybGlzdCA9IFtmLmZpbGVubygpIGZvciBmIGluIFtzeXMuc3RkaW4sIHAuc3Rkb3V0XV0Kd2hpbGUgcmxpc3Q6ICMgd2hpbGUgbm90IEVPRgogICAgZm9yIGZkIGluIHNlbGVjdChybGlzdCwgW10sIFtdLCB0aW1lb3V0KVswXToKICAgICAgICBpbnB1dF9kYXRhID0gb3MucmVhZChmZCwgNTEyKQogICAgICAgIHNvdXJjZSA9ICJzdGRpbiIgaWYgZmQgPT0gc3lzLnN0ZGluLmZpbGVubygpIGVsc2UgInN1YnByb2Nlc3MiCiAgICAgICAgcHJpbnQoImdvdCAlciBmcm9tICVzIiAlIChpbnB1dF9kYXRhLCBzb3VyY2UpKQogICAgICAgIGlmIG5vdCBpbnB1dF9kYXRhOiAjIEVPRgogICAgICAgICAgICBybGlzdC5yZW1vdmUoZmQpCnAuc3Rkb3V0LmNsb3NlKCkKcC53YWl0KCk=

YQpiCmMKZAo=

a
b
c
d