"""
Running this script on the following platforms triggers
a race condition in popen2 and subprocess modules:

Python 2.3.3 (#1, Feb 10 2004, 17:28:29)
[GCC 3.2.3 20030502 (Red Hat Linux 3.2.3-24)] on linux2

and

Python 2.3.5 (#1, Mar 30 2005, 17:01:57)
[GCC 3.2.3 20030502 (Red Hat Linux 3.2.3-49)] on linux2

and

Python 2.4.1 (#1, Apr 15 2005, 12:58:11)
[GCC 3.2.3 20030502 (Red Hat Linux 3.2.3-34)] on linux2

and

Python 2.4.1 (#1, Apr 15 2005, 13:32:19)
[GCC 2.95.2 19991024 (release)] on sunos5


I got no error here on this platform:

Python 2.3.5 (#1, Apr  6 2005, 11:30:31)
[GCC 2.96 20000731 (Red Hat Linux 7.3 2.96-113)] on linux2

"""
import optparse
import popen2 
import sys
import threading


class test_popen2(threading.Thread):
    def __init__(self):
        threading.Thread.__init__(self)

    def run (self):
        for i in range(5):
            pipe = popen2.Popen4("ls > /dev/null")
            pipe.wait()
            
class test_subprocess(threading.Thread):
    def __init__(self):
        threading.Thread.__init__(self)

    def run (self):
        import subprocess
        for i in range(5):
            pipe = subprocess.Popen("ls > /dev/null")
            pipe.wait()


def main(argv):
    """
    Provoke the Popen bug.
    """
    usage = "usage: %prog"
    parser = optparse.OptionParser(usage)
    parser.add_option("-n", action="store",type="int", dest="num_threads", help="start NUM_THREADS threads", default=20)
    parser.add_option("-s", action="store_true", dest="subprocess", help="Use subprocess instead of popen2", default=False)

    (options, args) = parser.parse_args(argv)

    if options.subprocess:
        worker = test_subprocess
    else:
        worker = test_popen2

    for i in range(options.num_threads):
        t = worker()
        t.start ()
        
    print "Started %d threads" % options.num_threads


if __name__ == '__main__':
    main(sys.argv[1:])