June 15, 2017

xxd reverse with an offset

When using xxd to reverse a hex dump file, if you hexdump file has a non-0 offset like this:

bc000000: 01 02 03 04 05 06 07 08  ........

You would need to use the "-s offset" option of the xxd. However, there is a bug in the code that makes this options only works as the FIRST option. Otherwise, it wouldn't work.

You want to do this:

xxd -s -0xbc000000 -r -g 1 test.dump test.bin

Basically the xxd is hardcoded to look for the offset at argv[2].

Another alternative: