mirror of https://github.com/python/cpython
69 lines
1.4 KiB
Python
69 lines
1.4 KiB
Python
"""This test checks for correct fork() behavior.
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We want fork1() semantics -- only the forking thread survives in the
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child after a fork().
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On some systems (e.g. Solaris without posix threads) we find that all
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active threads survive in the child after a fork(); this is an error.
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"""
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import os, sys, time, thread
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try:
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os.fork
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except AttributeError:
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raise ImportError, "os.fork not defined -- skipping test_fork1"
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LONGSLEEP = 2
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SHORTSLEEP = 0.5
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NUM_THREADS = 4
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alive = {}
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stop = 0
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def f(id):
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while not stop:
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alive[id] = os.getpid()
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try:
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time.sleep(SHORTSLEEP)
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except IOError:
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pass
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def main():
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for i in range(NUM_THREADS):
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thread.start_new(f, (i,))
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time.sleep(LONGSLEEP)
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a = alive.keys()
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a.sort()
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assert a == range(NUM_THREADS)
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prefork_lives = alive.copy()
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cpid = os.fork()
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if cpid == 0:
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# Child
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time.sleep(LONGSLEEP)
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n = 0
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for key in alive.keys():
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if alive[key] != prefork_lives[key]:
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n = n+1
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os._exit(n)
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else:
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# Parent
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spid, status = os.waitpid(cpid, 0)
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assert spid == cpid
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assert status == 0, "cause = %d, exit = %d" % (status&0xff, status>>8)
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global stop
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# Tell threads to die
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stop = 1
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time.sleep(2*SHORTSLEEP) # Wait for threads to die
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main()
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