#!/usr/pkg/bin/python2.7
# Copyright (c) 2002 ekit.com Inc (http://www.ekit-inc.com/)
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# $Id: locking.py,v 1.8 2004-02-11 23:55:09 richard Exp $

'''This module provides a generic interface to acquire and release
exclusive access to a file.

It should work on Unix and Windows.
'''
__docformat__ = 'restructuredtext'

from roundup.backends import portalocker

def acquire_lock(path, block=1):
    '''Acquire a lock for the given path
    '''
    file = open(path, 'w')
    if block:
        portalocker.lock(file, portalocker.LOCK_EX)
    else:
        portalocker.lock(file, portalocker.LOCK_EX|portalocker.LOCK_NB)
    return file

def release_lock(file):
    '''Release our lock on the given path
    '''
    portalocker.unlock(file)
