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Based on kernel version 3.16. Page generated on 2014-08-06 21:39 EST.

1	BFS FILESYSTEM FOR LINUX
2	========================
3	
4	The BFS filesystem is used by SCO UnixWare OS for the /stand slice, which
5	usually contains the kernel image and a few other files required for the
6	boot process.
7	
8	In order to access /stand partition under Linux you obviously need to
9	know the partition number and the kernel must support UnixWare disk slices
10	(CONFIG_UNIXWARE_DISKLABEL config option). However BFS support does not
11	depend on having UnixWare disklabel support because one can also mount
12	BFS filesystem via loopback:
13	
14	# losetup /dev/loop0 stand.img
15	# mount -t bfs /dev/loop0 /mnt/stand
16	
17	where stand.img is a file containing the image of BFS filesystem. 
18	When you have finished using it and umounted you need to also deallocate
19	/dev/loop0 device by:
20	
21	# losetup -d /dev/loop0
22	
23	You can simplify mounting by just typing:
24	
25	# mount -t bfs -o loop stand.img /mnt/stand
26	
27	this will allocate the first available loopback device (and load loop.o 
28	kernel module if necessary) automatically. If the loopback driver is not
29	loaded automatically, make sure that you have compiled the module and
30	that modprobe is functioning. Beware that umount will not deallocate
31	/dev/loopN device if /etc/mtab file on your system is a symbolic link to
32	/proc/mounts. You will need to do it manually using "-d" switch of
33	losetup(8). Read losetup(8) manpage for more info.
34	
35	To create the BFS image under UnixWare you need to find out first which
36	slice contains it. The command prtvtoc(1M) is your friend:
37	
38	# prtvtoc /dev/rdsk/c0b0t0d0s0
39	
40	(assuming your root disk is on target=0, lun=0, bus=0, controller=0). Then you
41	look for the slice with tag "STAND", which is usually slice 10. With this
42	information you can use dd(1) to create the BFS image:
43	
44	# umount /stand
45	# dd if=/dev/rdsk/c0b0t0d0sa of=stand.img bs=512
46	
47	Just in case, you can verify that you have done the right thing by checking
48	the magic number:
49	
50	# od -Ad -tx4 stand.img | more
51	
52	The first 4 bytes should be 0x1badface.
53	
54	If you have any patches, questions or suggestions regarding this BFS
55	implementation please contact the author:
56	
57	Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
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