local_mutex 1.0

local mutex

#local_mutex
本地锁,通过fcntl针对文件加锁实现的. 需要强烈注意的是,多线程下是无效的,原因? [查看链接](http://xiaorui.cc)

#Usage:

最简单的例子,适合一个程序同时跑一个的场景.
```
import sys
from local_mutex import LocalMutex

try:
lock = LocalMutex('app.lock')
except LockError:
sys.exit('already running')

try:
print 'doing'
finally:
lock.release()
```

使用wait参数不停的试图获取Lock, 直到获取锁.
```
lock = LocalMutex('/var/run/app.lock', wait = True)
try:
print 'doing'
finally:
lock.release()
```

使用with关键词
```
with LocalMutex('app.lock', wait = True):
print 'doing'
```

如果是多线程环境,直接用threading的Lock
```
import threading
lock = threading.Lock()
with lock:
pass
```