I thought PHP_SELF is availeble everywhere (or was it $SCRIPT_NAME)
script_name name is CGI environmental, I bet it´s not available
running ISAPI, __FILE__ is the best, it´s available from
everywhere regardless of php.ini configs and so on, but
it only tells the name of the current script being processed.
I don´t use it too, although it does not do what it promises
"A virtual path to the script being executed, used for self-referencing URLs."
well, in my phpinfo() I get this "/php4/php.exe"
and that´s useless information for self-referencing URLS of PHP type.