Upgrading from PHP2 to PHP4

[Anon]

I would like to upgrade from PHP2 to PHP4 as I'm writing new scripts that are not working, but think part of the problem is that I'm using books meant for PHP4. Can I skip over PHP3 and go directly to PHP4?

I have many scripts currently running on PHP2 what implications will an upgrade to PHP4 have these scripts.

Looking forward to any and all advice.

Thanks

[Anon]

Can't comment on PHP2 (never seen it!) but there are enough differences with php3 vs. php4 that you can't expect all functions to work the same.

Some even work rather differently - cookies for example. In PHP3, you had to do cookie-stuff backwards!

Of course, material that deals with cookies under PHP3 will be broken when upgrading to 4.0.

That said, when push comes to shove, php4.0 offers so much functionality beyond 3.x, and I'd imagine that the same is true from 3.x to 2.x, I'd highly recommend upgrading immediately if you are at all serious about doing meaningful work.

-Ben