Thanks Phil; I had figured it was something like that and I wondered what sort of overhead I was looking at. I've got a script that creates an iso9660 image every night as a bootable linux image, and I was starting to hit the outer limits of what would burn. According to my calculation, I should have been able to burn 681574400 bytes on a 650MB disk, but my ISO image clocked in at 662517760. I wanted a number to put in my script that errored out and deleted the image if it was too big to actually burn, so I thought maybe there was a specific number that I could be sure of across all media (obviously, someone selling disks labeled as 650M that would only hold 500 would be in bad shape). Guess I'm not going to be able to get that last few megs out of it. Jer Smith --------------------------------------------------------------------- To unsubscribe, e-mail: tclug-list-unsubscribe at mn-linux.org For additional commands, e-mail: tclug-list-help at mn-linux.org