Permission denied for SplFileObject

I'm running php 5.3.8, on xampp (the 开发者_StackOverflownewest version, 1.7.7 I believe), on Windows7 64bit. When I try to construct a SplFileObject giving it a directory path I get following message (both in read, or write mode):

failed to open stream: Permission denied

The folder exists, and I set proper rights (remember I'm on the Windows, not Linux). Can it be a problem with xampp - for example windows don't allow apache process to write anywhere on disk?