address@hidden (Antonio Diaz Diaz) wrote:
Hello Jason,
Jason Reeve wrote:
Unfortunately I never started ddrescue with a log file, so if I do stop
it, am I right in thinking I may have to start the whole process again
if the DMG is unusable?
You are right. Never start a rescue without a logfile. If everithing
goes well it is easy to delete the logfile afterwards, but if there are
errors the logfile can be very useful.
Indeed. But it would not be difficult to write a small program
that reads an image file and creates a logfile which is better
than nothing. It would simply assume that sectors containng
all zeros were unrecovered.
If you want to write such a program, Jason, you could use my
little sparsecopy.c program as a starting point, since it
already reads an image file and checks each sector to see
whether it is all zeros. It is a small, quick-and-dirty
program, but it works; get it from
http://www.burtonsys.com/download/ddr2sr.zip
Hmmmm... in Linux, is there any way to tell the difference
between a block of zeros which is stored on the disk and a
block of zeros which is NOT stored (in a sparse file)? If so,
it should be possible to create an excellent logfile from the
image file! Does anyone know how to do this?
-Dave