write-byte
byte stream => byte
byte--an integer of the stream element type of stream.
stream--a binary output stream.
write-byte writes one byte, byte, to stream.
(with-open-file (s "temp-bytes" :direction :output :element-type 'unsigned-byte) (write-byte 101 s)) => 101
stream is modified.
The element type of the stream.
Should signal an error of type type-error if stream is not a stream. Should signal an error of type error if stream is not a binary output stream.
Might signal an error of type type-error if byte is not an integer of the stream element type of stream.