twisted.python.lockfile.FilesystemLock : API documentation

class documentation

class twisted.python.lockfile.FilesystemLock: (source)

Known subclasses: twisted.internet.defer.DeferredFilesystemLock

A mutex.

This relies on the filesystem property that creating a symlink is an atomic operation and that it will fail if the symlink already exists. Deleting the symlink will release the lock.

Instance Variable	name	The name of the file associated with this lock.
Instance Variable	clean	Indicates whether this lock was released cleanly by its last owner. Only meaningful after `lock` has been called and returns True.
Instance Variable	locked	Indicates whether the lock is currently held by this object.
Method	__init__	Undocumented
Method	lock	Acquire this lock.
Method	unlock	Release this lock.

name = (source)

The name of the file associated with this lock.

clean = (source)

Indicates whether this lock was released cleanly by its last owner. Only meaningful after lock has been called and returns True.

locked = (source)

Indicates whether the lock is currently held by this object.

(type: bool)

def __init__(self, name): (source)

overridden in twisted.internet.defer.DeferredFilesystemLock

Undocumented

def lock(self): (source)

Acquire this lock.

Returns	True if the lock is acquired, false otherwise. (type: `bool`)
Raises	OSError	Any exception `os.symlink()` may raise, other than `errno.EEXIST`.

def unlock(self): (source)

Release this lock.

This deletes the directory with the given name.

Raises	OSError	Any exception `os.readlink()` may raise.
	ValueError	If the lock is not owned by this process.

API Documentation for Twisted, generated by pydoctor 20.12.1 at 2021-02-28 19:53:36.