Re: Should "diff" on binary files throw an exit code 2?

[Paul Eggert]

In general, plain "diff" should probably return some sort of problem
indication when given a binary file, since the output is not suitable
as a patch.

One workaround is to invoke "cmp -s a b" if "diff" exits with status
2, and to use cmp's exit status to decide whether there was real
trouble.

Another possibility would be to add a new option to "diff", but
someone would have to think that through.