(or(atomerr)*allow-no-checksums*));;returning NIL to the listener stops, t lets it continue. err will only be not atom() if it's a warning, which are handled differently. T lets the pipe continue and pass the message to the message callback, nil does not.
(formatt" <- (~a) ~a (size: ~a)~%"type(sipc:pointer-to-arraymessage)(sipc:pointer-sizemessage));;print the binary message as an array of bytes, the type, & the size
(formatt" <- (~a) ~a~%"typemessage));;print the message & type