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.