import os
import subprocess

from time import time
print("pid: %s" % os.getpid())
a=time()
for i in range(10000):
    if 0:
        # 19081.1 ms
        pid = os.fork()
        if pid == 0:
            os.execv("/bin/false", ["/bin/false"])
        else:
            os.waitpid(pid, 0)
    elif 0:
        # 25769.8 ms
        f = os.popen("/bin/false")
        f.close()
    elif 1:
        # unpatched: 40025.8 ms
        # patched:   26155.2 ms
        f = subprocess.Popen(["/bin/false"], shell=False)
        f.wait()
b=time()-a
print("Time: %.1f ms" % (b*1000))