bindiff is half of a two part solution for synchronising 
binary files.

Its a implementation of the rsync algorithm as a patch/diff 
style utility.  (See Dr Andrew Tridgell's thesis, "Efficient
Algoritms for Sorting and Synchronization", for more details.)

bindiff provides the 'diff' half, whereas binpatch will provide
the 'patch' half.

bindiff output files are also quite large as its a 7bit ascii
format.  (binary segments are encoded using base64).  Running
the output through gzip is probably a good idea.  Future versions
of bindiff may abandon this format in favour of a lighter weight
format.

Whilst I've made every effort to implement the algorithm
correctly, there may still be some bugs left.  I currently can
not confirm correct operation (beyond the results looking right)
and won't be able to until I've finished writing binpatch.

- Chris Collins <xfire-plan9@xware.cx>  10 Oct 2005