New stream wrappers
New Class Constants
Migrating from PHP 5.2.x to PHP 5.3.x
PHP Manual
New stream filters
The following stream filters were introduced in 5.3.0:
dechunk (reverses HTTP chunked encoding)
The bz2.decompress filter now supports concatenation.
New stream wrappers
New Class Constants
Migrating from PHP 5.2.x to PHP 5.3.x
PHP Manual