Peace.

% uname -srm
NetBSD 1.2G i386
% alias hd hexdump -e \''"%06_ax " 16/1 " %02x"'\'\
                 -e \''"  " "%_p"'\' -e \''"\n"'\'
% alias hd
hexdump -e '"%06_ax " 16/1 " %02x"' -e '"  " "%_p"' -e '"\n"'
% hd -s 32 /usr/mdec/biosboot.sym | head -2
000020  66 ea 08 00 00 00 c0 07 8c c8 8e d8 66 b8 00 01  f...........f...
000030  00 00 8e d0 66 bc fc ff 00 00 8e c0 80 fa 80 66  ....f..........f
% whoami
root
% disklabel -r sd0 > protofile
% egrep '^#|^  [ac]:' protofile
# /dev/rsd0d:
#        size   offset    fstype   [fsize bsize   cpg]
  a:    65536   491520    4.2BSD     1024  8192    16 	# (Cyl.  240 - 271)
  c:  3686400   491520    unused        0     0       	# (Cyl.  240 - 2039)
% dd if=/dev/rsd0a of=xxx count=16
16+0 records in
16+0 records out
8192 bytes transferred in 1 secs (8192 bytes/sec)
% hd xxx | head -2
000000  66 ea 08 00 00 00 c0 07 8c c8 8e d8 66 b8 00 01  f...........f...
000010  00 00 8e d0 66 bc fc ff 00 00 8e c0 80 fa 80 66  ....f..........f
% 
% man disklabel | col -b | sed -n 75,80p
     With the -R flag, disklabel is capable of restoring a disk label that was
     formatted in a prior operation and saved in an ascii file.	 The prototype
     file used to create the label should be in the same format as that pro-
     duced when reading or editing a label.  Comments are delimited by # and
     newline.  As with -w, any existing bootstrap code will be clobbered if -r
     is specified and will be unaffected otherwise.
% disklabel -Rr sd0 ./protofile
% dd if=/dev/rsd0a of=xxx count=16
16+0 records in
16+0 records out
8192 bytes transferred in 1 secs (8192 bytes/sec)
% hd xxx
000000  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
*
000200  57 45 56 82 04 00 00 00 6d 79 73 64 00 00 00 00  WEV.....mysd....
000210  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
000220  00 00 00 00 00 00 00 00 00 02 00 00 20 00 00 00  ............ ...
000230  40 00 00 00 f8 07 00 00 00 08 00 00 00 c0 3f 00  @.............?.
000240  00 00 00 00 00 00 00 00 10 0e 01 00 00 00 00 00  ................
000250  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
*
000280  00 00 00 00 57 45 56 82 a8 52 08 00 00 20 00 00  ....WEV..R... ..
000290  00 20 00 00 00 00 01 00 00 80 07 00 00 04 00 00  . ..............
0002a0  07 08 10 00 00 80 01 00 00 80 08 00 00 00 00 00  ................
0002b0  01 00 00 00 00 40 38 00 00 80 07 00 00 00 00 00  .....@8.........
0002c0  00 00 00 00 00 c0 3f 00 00 00 00 00 00 00 00 00  ......?.........
0002d0  00 00 00 00 00 00 26 00 00 00 0a 00 00 04 00 00  ......&.........
0002e0  07 08 10 00 00 c0 08 00 00 00 32 00 00 04 00 00  ..........2.....
0002f0  07 08 10 00 e0 bf 03 00 20 00 00 00 00 00 00 00  ........ .......
000300  08 00 00 00 e0 bf 03 00 20 c0 03 00 00 00 00 00  ........ .......
000310  08 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
000320  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
*
% 

Not peace.

% /usr/mdec/installboot /usr/mdec/biosboot.sym /dev/rsd0a
% dd if=/dev/rsd0a of=xxx count=16
16+0 records in
16+0 records out
8192 bytes transferred in 1 secs (8192 bytes/sec)
% hd xxx | head -2
000000  66 ea 08 00 00 00 c0 07 8c c8 8e d8 66 b8 00 01  f...........f...
000010  00 00 8e d0 66 bc fc ff 00 00 8e c0 80 fa 80 66  ....f..........f
% 

Peace.

Hiroyuki Ito