Metadata-Version: 1.1
Name: zc.lockfile
Version: 1.0.0
Summary: Basic inter-process locks
Home-page: http://www.python.org/pypi/zc.lockfile
Author: Jim Fulton
Author-email: jim@zope.com
License: ZPL 2.1
Description: *************************
        Basic inter-process locks
        *************************
        
        The zc.lockfile package provides a basic portable implementation of
        interprocess locks using lock files.  The purpose if not specifically
        to lock files, but to simply provide locks with an implementation
        based on file-locking primitives.  Of course, these locks could be
        used to mediate access to *other* files.  For example, the ZODB file
        storage implementation uses file locks to mediate access to
        file-storage database files.  The database files and lock file files
        are separate files.
        
        .. contents::
        
        Detailed Documentation
        **********************
        
        Lock file support
        =================
        
        The ZODB lock_file module provides support for creating file system
        locks.  These are locks that are implemented with lock files and
        OS-provided locking facilities.  To create a lock, instantiate a
        LockFile object with a file name:
        
            >>> import zc.lockfile
            >>> lock = zc.lockfile.LockFile('lock')
        
        If we try to lock the same name, we'll get a lock error:
        
            >>> import zope.testing.loggingsupport
            >>> handler = zope.testing.loggingsupport.InstalledHandler('zc.lockfile')
            >>> try:
            ...     zc.lockfile.LockFile('lock')
            ... except zc.lockfile.LockError:
            ...     print "Can't lock file"
            Can't lock file
        
            >>> for record in handler.records:
            ...     print record.levelname, record.getMessage()
            ERROR Error locking file lock; pid=UNKNOWN
        
        To release the lock, use it's close method:
        
            >>> lock.close()
        
        The lock file is not removed.  It is left behind:
        
            >>> import os
            >>> os.path.exists('lock')
            True
        
        Of course, now that we've released the lock, we can created it again:
        
            >>> lock = zc.lockfile.LockFile('lock')
            >>> lock.close()
        
        .. Cleanup
        
            >>> import os
            >>> os.remove('lock')
        
        
        Change History
        ***************
        
        1.0.0 (2008-10-18)
        ====================
        
        - Fixed a small bug in error logging.
        
        1.0.0b1 (2007-07-18)
        ====================
        
        Initial release
        
        Download
        **********************
        
Keywords: lock
Platform: UNKNOWN
Classifier: Programming Language :: Python
Classifier: Development Status :: 4 - Beta
Classifier: Intended Audience :: Developers
Classifier: License :: OSI Approved :: Zope Public License
Classifier: Operating System :: POSIX
Classifier: Operating System :: Microsoft :: Windows
