Apache "Request" Ids?

I am pretty sure I am dreaming here but .... I once wrote a locking tool for UNIX that kept as part of it's information the process ID. If another process went to grab the lock, one thing it would do was check if the process that had taken it was still running. If it wasn't, it knew it could safely take the lock. This of course won't work under PHP in it's module form because the process ID belongs to Apache. What I was wondering was there any kind of ID that was attached to a particular CGI request that I could access and use? Brian ------------------------- Brian White Step Two Designs Pty Ltd - SGML, XML & HTML Consultancy Phone: +612-93197901 Web: http://www.steptwo.com.au/ Email: bwhite@steptwo.com.au