Unix file permissions are one of the more difficult subjects to grasp.. Well, ok maybe "grasp" isn't the word.. Master is the right word.. Unix file permissions is a hard topic to fully master, mainly I think because there aren't many instances when a computer user encounters them seriously, and bitwise is oldschool. This contains a listing of all possible permission masks and bits from a linux, php, and web hosting view.... cuz you guys AskApache Regs Rock!
Security chmod File Permissions umask
The story behind this plugin is sorta wack, but in a good way :). While doing tons of security research on permissions, authorization, access, etc.. for the Password Protection plugin (still being worked on), I needed to have unheard of debugging capabilities while working on the plugin on the various websites, webhosts, and test servers that I use to test in different environments. So I hacked together a bunch of php code that helped me debug, actually I pretty much went overkill and tried to get as much debugging info as programmatically possible, and it ended up being so much code that I took it out of my Password Protection code and made it its own plugin.
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