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losetup loopdev

set up a loop device

Set up a loop device:

losetup [-o offset] [--sizelimit size] [-Pr] [--show] -f|loopdev file

Apparently I'm not supposed to use -P and -o together.

This command will tell you which loop device is currently unused. ~# losetup -f~

losetup /dev/loopN hd0.img

Alternatively losetup -o 1048576 --find --show hd0.img will also set up the loop device.