rmail-widen-to-current-msgbeg

rmail-widen-to-current-msgbeg is a compiled Lisp function in `rmail.el'.

(rmail-widen-to-current-msgbeg FUNCTION)

Call FUNCTION with point at start of internal data of current message.
Assumes that bounds were previously narrowed to display the message in Rmail.
The bounds are widened enough to move point where desired, then narrowed
again afterward.

FUNCTION may not change the visible text of the message, but it may
change the invisible header text.