Differences in 3 and 4

[Anon]

I have been using version 4 exclusively until now. One of my clients uses a hosting service that only provides 3, and they want to use this company with my products. Obviously I will test everything extensively, but I was wondering if there are any functions that I will be suprised to be without, mainly pertaining to MySQL and filesystem functions. String functions are used a lot too. It would just be easier to know what not to use from the start.

Thanks!
James

[smarlowe]

Every function lists in the documentation when it first showed up. Lots of array functions are new, as are some string functions.

I don't know of a definitive document that says which functions showed up when or anything.