$ curl cheat.sh/
# losetup
# Set up and control loop devices.
# More information: <https://manned.org/losetup>.

# List loop devices with detailed info:
losetup -a

# Attach a file to a given loop device:
sudo losetup /dev/loop /path/to/file

# Attach a file to a new free loop device and scan the device for partitions:
sudo losetup --show --partscan -f /path/to/file

# Attach a file to a read-only loop device:
sudo losetup --read-only /dev/loop /path/to/file

# Detach all loop devices:
sudo losetup -D

# Detach a given loop device:
sudo losetup -d /dev/loop

$
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