gistfile1.el

(defvar rcirc-max-message-length 420
  "Messages longer than this value will be split.")

(defun rcirc-send-message (process target message &optional noticep silent)
  "Send TARGET associated with PROCESS a privmsg with text MESSAGE.
If NOTICEP is non-nil, send a notice instead of privmsg.
If SILENT is non-nil, do not print the message in any irc buffer."
  ;; max message length is 512 including CRLF
  (let* ((response (if noticep "NOTICE" "PRIVMSG"))
         (oversize (> (length message) rcirc-max-message-length))
         (text (if oversize
                   (substring message 0 rcirc-max-message-length)
                 message))
         (text (if (string= text "")
                   " "
                 text))
         (more (if oversize
                   (substring message rcirc-max-message-length))))
    (rcirc-get-buffer-create process target)
    (rcirc-send-string process (concat response " " target " :" text))
    (unless silent
      (rcirc-print process (rcirc-nick process) response target text))
    (when more (rcirc-send-message process target more noticep))))