I'm an avid XAMPP user but this isn't strictly a xampp problem. I managed somehow to screw up OSX's built in PHP. Was trying to copy Zend Tool scripts into /usr/bin/php.
Now when I try and issue any php command such as php version I get this error :
/usr/bin/php: fork: Resource temporarily unavailable
I thought the xampp mac developers might have a clue what the problem might be.