rmail-show-message-1

rmail-show-message-1 is a compiled Lisp function in `rmail.el'.

(rmail-show-message-1 &optional MSG)

Show message MSG (default: current message) using `rmail-view-buffer'.
Return text to display in the minibuffer if MSG is out of
range (displaying a reasonable choice as well), nil otherwise.
The current mail message becomes the message displayed.