Backing up cds using a macbook and snow leopard

Our cleared checks come on a cd from the bank each month. The cds desperately needed to be backed up.  Here are the steps I used to accomplish.  


Using a macbook with snow leopard and a slashdot article on creating an iso from a cd slightly modified, I was able to accomplish this fairly easily.


First, find where the disc is located


drutil status


Look for the name output, which in my case was


/dev/disk1


On the slashdot article, they were able to dd /dev/disk1 but in my case I had to go one step further and first list the sessions


ls /dev/disk1*


which listed 


/dev/disk1 and /dev/disk1s0


Next unmount the cd using


diskutil unmountDisk /dev/disk1


and then create an iso file from the cd


dd if=/dev/disk1s0 of=file.iso bs=2048


I know this can be automated even further but I chose the long way and went through the steps for each cd. I was able to eliminate the drutil and ls commands on subsequent runs as /dev/disk1s0 remained constant with every cd.