Patches item #1744382, was opened at 2007-06-27 20:08 Message generated for change (Comment added) made by loewis You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=305470&aid=1744382&group_id=5470
Please note that this message will contain a full copy of the comment thread, including the initial issue submission, for this request, not just the latest update. Category: Modules Group: Python 2.6 Status: Open Resolution: None Priority: 5 Private: No Submitted By: Yaakov Nemoy (loupgaroublond) Assigned to: Nobody/Anonymous (nobody) Summary: Read Write lock Initial Comment: This is a Lock for handling both multiple readers and a single or multiple writers. It allows any number of readers to acquire a 'lock' via a modified semaphore. It also allows any number of writers to try to acquire a lock, which signals the lock to block new readers from acquiring, until the writers have had a chance to do their business. Through a simple lock, multiple writers can wait in line, although only one writer can actually write at a time. It also lets the developer use the 'with' statement, via methods that return contextmanagers. I actually had a couple of unimplemented ideas. A) Writers can specify a deadline (or even use a default) such that after the deadline passes, the lock can use a callback to rollback/kill/pause readers, so that the writer doesn't wait an eternity. B) Allowing the semaphore to have an upper limit of allowed readers (or anythings), Since I don't need it, i never programmed it, but it should be fairly trivial to implement if there is any demand. ---------------------------------------------------------------------- >Comment By: Martin v. Löwis (loewis) Date: 2007-06-30 19:38 Message: Logged In: YES user_id=21627 Originator: NO The patch is unacceptable in its current form: - it should be provided as a patch to threading.py, not as a separate module - it should have a name that follows "the convention", which seems to be that it should have "reader" and "writer" in its name (or "rw"). See how C# and Java do it (and other libraries you can find that provide such a mechanism) - it needs documentation - it needs tests. ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=305470&aid=1744382&group_id=5470 _______________________________________________ Patches mailing list Patches@python.org http://mail.python.org/mailman/listinfo/patches
