[Zope] Detecting dropped client connection?

Hi. I have a method that generates a large database report (around 4MB). It takes around 5 minutes to generate, but I can happily stream it to the client using RESPONSE.write(). What I have noticed, however, is that if the client drops the connection, my method just keeps processing oblivious wasting ram, cycles but most importantly a Zope thread. Is there a call I can make for my code to check if the connection is still valid, allowing it to die if nothing is listening to it? -- Stuart Bishop <zen@shangri-la.dropbear.id.au>