diff-sentinel

diff-sentinel is a compiled Lisp function in `diff.el'.

(diff-sentinel CODE &optional OLD-TEMP-FILE NEW-TEMP-FILE)

Code run when the diff process exits.
CODE is the exit code of the process. It should be 0 only if no diffs
were found.
If optional args OLD-TEMP-FILE and/or NEW-TEMP-FILE are non-nil,
delete the temporary files so named.