Re: Extracting directories from an ISO image, command line tool?

["Thomas Schmitt" <scdbackup@gmx.net>]

Hi,

Richard Owlett wrote:
> METHODOLOGY:
> Copy all DVDs to ISO 9660 conforming files
> [dd understood to be correct tool].

dd, libc, the kernel or whatever on your system seems to have
a bug with readable size of DVDs. This size seems not to change
when a new DVD is loaded into the drive.

Nevertheless, /sys indicates that the correct size is perceived
by the kernel at least in some of its parts. So there is some
hope that libburn (via xorriso) and the drive could team up
to retrieve all data from the DVD.

See my proposal 

  xorriso -indev /dev/sr0 \
          -check_media data_to="$FILENAME" --

in
  https://lists.debian.org/debian-user/2015/09/msg00890.html


> Copy the resulting files to USB device for convenient loop mounting.
> As loop mounting 13 (or more) files can be cumbersome, use xorriso
> to process *.iso to obtain complete repository on a single USB device.

xorriso may also extract the files directly from DVD:

  xorriso -osirrox on:auto_chmod_on -overwrite nondir \
          -indev /dev/sr0 \
          -extract /pool /media/richard/REPO8/test/pool

This will use SG_IO for communication with the drive,
like above -check_media proposal.

It would be interesting to see what happens when the ISO 9660
filesystem driver tries to read blocks which read(2) is not
willing to read. I.e. the way of "mount" and "cp".


Have a nice day :)

Thomas