Purge temp files automatically?

Im doing some photo manipulation with mini-magick.

Sometimes, in one action, it will work on 15+ photos and create like 40+
temp files. It seems that the temp files will get deleted while the
action is happening.

This causes about 1 out of 10 photos to trigger an error since the temp
file containing the photo information gets deleted before it finishes
working with it.

Has anyone seen this happen before?