Mounting self-made cloop file - how?

[fredvej]

I make a cloop file directly from the mounted file system like this:

$ genisoimage -input-charset ISO-8859-15 -R -l -D -V KNOPPIX_FS -quiet \
  -no-split-symlink-components -no-split-symlink-fields \
  -hide-rr-moved -cache-inodes /path/to/cloop/filesystem/root/directory \
  | create_compressed_fs -q -B 65536 -t 8 -L 9 \
  -f /tmp/isotemp - /path/to/created/cloop/file

I don't know if your creation method with ddrescue and create_compressed_fs does the same.
Does the method below work for you?

$ sudo losetup --verbose --read-only  /dev/cloop7 /mnt-system/KNOPPIX/KNOPPIX1
losetup: /mnt-system/KNOPPIX/KNOPPIX1: Warning: file does not fit into a 512-byte sector; the end of the file will be ignored.

$ sudo mount --verbose  /dev/cloop7  /mnt-user
mount: /dev/cloop7 is write-protected, mounting read-only
mount: /dev/cloop7 mounted on /mnt-user.

$ sudo blkid | grep cloop7
/dev/cloop7: UUID="2016-10-22-16-00-20-00" LABEL="KNOPPIX_ADDONS1" TYPE="iso9660"

$ df | grep cloop7
/dev/cloop7      1033766   1033766         0 100% /mnt-user

Since Knoppix 7 I cannot find a way to detach the cloop device again, so I have to reboot to release the device.

$ sudo umount --verbose  /dev/cloop7
umount: /mnt-user (/dev/cloop7) unmounted

$ sudo losetup --verbose --detach  /dev/cloop7
losetup: /dev/cloop7: failed to use device: No such device

$ sudo blkid | grep cloop7
/dev/cloop7: UUID="2016-10-22-16-00-20-00" LABEL="KNOPPIX_ADDONS1" TYPE="iso9660"