Evert Pot has posted about a library he's creating to integrate WebDAV support with PHP and make things simpler for those needing to access the shares.

I intend to make this library as easy as possible to use, without making it a black-box-like system. Focus will not be on everything WebDAV could possibly provide, but instead on the features that are actually supported by the operating systems.

His goal is to make it as simple as making a 'File' and 'Directory' class to interface with the remote system and has two things he's deliberating on as far as features to include in the library - support for the custom properties WebDAV allows and the ability to lock files and directories.

If you'd like to check out the current progress of the library, check out its page on the Google Code site (as well as this discussion group he's set up).

Race conditions in applications can be one of the hardest things to work out the kinks on, especially in a more complex application you're adding the new functionality to. One such instance comes up when you add Ajax functionality into the mix. Because of its asynchronous nature, it can cause a race condition version easily. Andy Bakun has been there and done that in his code and has found some helpful hints he's sharing in this (info packed) post over on his blog.

One of the problem with race conditions is that it is often difficult to actually witness the ramifications of one when it happens, especially if you are not aware of it. If you've used PHP's built-in, default session handling (that uses files), you'll never come across the problem. However, things get interesting once you start using session_set_save_handler to write your own session handler.

He breaks it down into some more manageable chunks:

• A Multi-processing but non-Threaded Environment
• The Default PHP Session Handler
• Observing the Race Condition
• The Demo App Interface
• Resource Contention
• Minimizing Lock Holding Time
• Why is per-variable locking important?
• Rolling Your Own Session Handler
• The Code

See? You didn't believe me when I said it was long...there's tons of great info in there about working with sessions in PHP and how to get Ajax to play nice when manipulating the data inside them. There's plenty of test code and some sidebars with additional information to keep you reading for a while. Be sure to check this one out, even if you're just working with PHP sessions and Ajax and don't have a race condition issue in your app - never hurts to be prepared.

On phpied.com today, there's their look at their needs in a phpBB module - and how they ended up solving it on their own.

I had this request to implement a feature on a phpBB board whereby topics older than one month to get deleted. A quick search on phpbbhacks.com revealed a result - Auto Lock hack, but it had a disturbing note saying that it's not recommended for larger boards, although I couldn't figure out why. Anyway, the hack looked too involved, with DB changes, new Admin Panel options, etc., so I decided to hack something together quickly. Turned out to be pretty easy. Here' s the result.

Their version uses a simple SQL statement to do a perioding update on the table, marking the ones over a month old as locked. If the update fails, an email is sent. Then, so that no cron job would be needed to make these updates, a semi-random item was placed in the page to run when the user accesses it normally...