|Linux & Unix Commands - Search Man Pages
LOSETUP(8) MAINTENANCE COMMANDS LOSETUP(8)
losetup - set up and control loop devices
losetup [ -e encryption ] [ -o offset ] loop_device file
losetup [ -d ] loop_device
losetup is used to associate loop devices with regular files or block devices, to detach
loop devices and to query the status of a loop device. If only the loop_device argument is
given, the status of the corresponding loop device is shown.
-d detach the file or device associated with the specified loop device.
enable data encryption. The following keywords are recognized:
NONE use no encryption (default).
XOR use a simple XOR encryption.
DES use DES encryption. DES encryption is only available if the optional DES
package has been added to the kernel. DES encryption uses an additional
start value that is used to protect passwords against dictionary attacks.
the data start is moved offset bytes into the specified file or device.
losetup returns 0 on success, nonzero on failure. When losetup displays the status of a
loop device, it returns 1 if the device is not configured and 2 if an error occurred which
prevented losetup from determining the status of the device.
/dev/loop0,/dev/loop1,... loop devices (major=7)
If you are using the loadable module you must have the module loaded first with the com-
# insmod loop.o
The following commands can be used as an example of using the loop device.
dd if=/dev/zero of=/file bs=1k count=100
losetup -e des /dev/loop0 /file
Init (up to 16 hex digits):
mkfs -t ext2 /dev/loop0 100
mount -t ext2 /dev/loop0 /mnt
losetup -d /dev/loop0
If you are using the loadable module you may remove the module with the command
# rmmod loop
DES encryption is painfully slow. On the other hand, XOR is terribly weak.
Original version: Theodore Ts'o <firstname.lastname@example.org>
Original DES by: Eric Young <email@example.com>
Linux Nov 24 1993 LOSETUP(8)
All times are GMT -4. The time now is 05:04 PM.