A while back I came across the hexdump utility, which allows you to dump the contents of a device or file in hexadecimal:
$ dd if=/dev/hda count=1 | hexdump -x
1+0 records in 1+0 records out 0000000 48eb 1090 d08e 00bc b8b0 0000 d88e c08e 0000010 befb 7c00 00bf b906 0200 a4f3 21ea 0006 0000020 be00 07be 0438 0b75 c683 8110 fefe 7507 0000030 ebf3 b416 b002 bb01 7c00 80b2 748a 0203 0000040 0080 8000 e051 0001 0800 80fa 80ca 53ea
This is a super useful utility!
The -C option outputs per-byte data, which can be more helpful sometimes:
00000000 2f 2a 0a 20 2a 20 41 6d 61 6e 64 61 2c 20 54 68 |/*. * Amanda, Th|
00000010 65 20 41 64 76 61 6e 63 65 64 20 4d 61 72 79 6c |e Advanced Maryl|
00000020 61 6e 64 20 41 75 74 6f 6d 61 74 69 63 20 4e 65 |and Automatic Ne|
00000030 74 77 6f 72 6b 20 44 69 73 6b 20 41 72 63 68 69 |twork Disk Archi|
00000040 76 65 72 0a 20 2a 20 43 6f 70 79 72 69 67 68 74 |ver. * Copyright|
Or you can use “od” which will probably be found on more systems (including AIX, HPUX, and Solaris). “od -x” and “od -c” are 2 fairly useful ones.
Jeff Schroeder on December 5th, 2009
When in vi, try this to convert to hex:
%!xxd
Edit whatever you want and then to change back to binary do:
%!xxd -r
An old solaris guy taught me that nifty trick.