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#!/usr/bin/env python
# Copyright (C) 2020 Red Hat, Inc. <http://www.redhat.com>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License along
# with this program; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
from fcntl import flock, LOCK_EX, LOCK_NB, LOCK_UN
from time import sleep
from argparse import ArgumentParser
def get_file_lock(args):
"""
Gets the lock to a file and releases it after timeout
"""
file_name = args.f
timeout = args.t
f = open(file_name, 'w')
flock(f.fileno(), LOCK_EX | LOCK_NB)
sleep(int(timeout))
flock(f.fileno(), LOCK_UN)
if __name__ == "__main__":
file_lock_parser = ArgumentParser(
prog="file_lock.py", description="Program to validate file lock ops")
file_lock_req_args = file_lock_parser.add_argument_group(
'required named arguments')
file_lock_req_args.add_argument(
'-f', type=str, required=True,
help="File on which lock has to be applied")
file_lock_req_args.add_argument(
'-t', help="time for which lock has to be retained", type=int,
required=True)
file_lock_parser.set_defaults(func=get_file_lock)
args = file_lock_parser.parse_args()
rc = args.func(args)
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