28 lines
617 B
Python
28 lines
617 B
Python
"""
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Interprocess mutex based on file locks
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"""
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import fcntl
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import os
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class Lock:
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def __init__(self, filename):
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self.filename = filename
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# This will create it if it does not exist already
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unbuffered = 0
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self.handle = open(filename, 'a+', unbuffered)
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def acquire(self):
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fcntl.flock(self.handle, fcntl.LOCK_EX)
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# will throw IOError if unavailable
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def try_acquire(self):
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fcntl.flock(self.handle, fcntl.LOCK_NB | fcntl.LOCK_EX)
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def release(self):
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fcntl.flock(self.handle, fcntl.LOCK_UN)
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def __del__(self):
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self.handle.close()
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