[OT] Making images from CDs

["Thomas J. Hamman" <hawk3@eagnet.com>]

First, a simple question:  What is the correct command-line way of
copying a CD to an image file on the hard drive?  Is a simple "dd
if=/dev/cdrom of=cd.img" command sufficient?  Or do I need to run
mkisofs using the directory of a mounted CD as the root directory of the
image?  I already know how to use cdrecord to burn the image,
fortunately.

Now, a tougher problem:  I received an "Input/output error" while trying
to copy a CD to an image file (using xcdroast, and I also got the error
while trying dd).  I tried another CD and it worked fine, so I'm
guessing the problem is the particular CD.  The CD does work fine,
however.  So, what I'm wondering is whether or not there is anyway
around such an error, or whether it would be worthwhile to go ahead and
burn the resulting image and hope it works.

-- 
Thomas J. Hamman
"Science without religion is lame, religion without science is blind."
        -Albert Einstein