MemoryMangement?

Greeting all, So I've been looking for some functions in PHP that will report the memory used by a script (I used to know this). The reason is I am working on a personal picture gallery package in PHP and was using this package, http://www.offsky.com/software/exif/index.php, to extract the EXIF information from my photos for display. My ISP doe not allow the EXIF libs on the default PHP install so I was looking for a pure PHP alternative. This EXIF package is pure PHP. What I am running into is this. I have a readdir loop and a call for each file to the EXIF package. After about 15 files processed I get an error about 'emalloc could not allocate XXXXXX bytes of memory'. I looked at the EXIF package and didn't find anything. The package (via function call) returns an array. I have added an unset to the return reference once I have finished but still get the error. Note: I am not asking for help with the EXIF package. Just wondering about some memory monitoring functions in PHP. Thanks, Paul