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+The BFS filesystem is used by SCO UnixWare OS for the /stand slice, which
+usually contains the kernel image and a few other files required for the
+boot process.
+In order to access /stand partition under Linux you obviously need to
+know the partition number and the kernel must support UnixWare disk slices
+(CONFIG_UNIXWARE_DISKLABEL config option). However BFS support does not
+depend on having UnixWare disklabel support because one can also mount
+BFS filesystem via loopback:
+# losetup /dev/loop0 stand.img
+# mount -t bfs /dev/loop0 /mnt/stand
+where stand.img is a file containing the image of BFS filesystem.
+When you have finished using it and umounted you need to also deallocate
+/dev/loop0 device by:
+# losetup -d /dev/loop0
+You can simplify mounting by just typing:
+# mount -t bfs -o loop stand.img /mnt/stand
+this will allocate the first available loopback device (and load loop.o
+kernel module if necessary) automatically. If the loopback driver is not
+loaded automatically, make sure that your kernel is compiled with kmod
+support (CONFIG_KMOD) enabled. Beware that umount will not
+deallocate /dev/loopN device if /etc/mtab file on your system is a
+symbolic link to /proc/mounts. You will need to do it manually using
+"-d" switch of losetup(8). Read losetup(8) manpage for more info.
+To create the BFS image under UnixWare you need to find out first which
+slice contains it. The command prtvtoc(1M) is your friend:
+# prtvtoc /dev/rdsk/c0b0t0d0s0
+(assuming your root disk is on target=0, lun=0, bus=0, controller=0). Then you
+look for the slice with tag "STAND", which is usually slice 10. With this
+information you can use dd(1) to create the BFS image:
+# umount /stand
+# dd if=/dev/rdsk/c0b0t0d0sa of=stand.img bs=512
+Just in case, you can verify that you have done the right thing by checking
+the magic number:
+# od -Ad -tx4 stand.img | more
+The first 4 bytes should be 0x1badface.
+If you have any patches, questions or suggestions regarding this BFS
+implementation please contact the author:
+Tigran A. Aivazian <>