mail-signature
mail-signature is an interactive compiled Lisp function in `sendmail.el
'.
(mail-signature &optional ATPOINT)
Sign letter with signature.
If the variable `mail-signature' is a string, inserts it.
If it is t or nil, inserts the contents of the file `mail-signature-file'.
Otherwise, evals `mail-signature'.
Prefix argument ATPOINT means insert at point rather than the end.