Wiping a disk is probably better done on the disk level, not the filesystem level. Write some stuff (random, just zeroes or just ones) at the disk device instead of the mount point.

If you still want to go with your procedure you can use the "mount" command to find out where the filesystems are mounted. It always looks a little different from system to system, so there is no general line i could give you, but surely you can figure out some parsing schema once you see it. A simple way to read a tablelike output would be (replace "<b>" and "<t>" with literal blanks/tabs when you write it):

Code:

mount | sed 's/[<b><t>][<b><t>]*/<b>/g' | while read var1 var2 var3 ... ; do
     <whatever you want to do with the filesystems here>
done

I hope this helps.

bakunin