mh-truncate-log-buffer
mh-truncate-log-buffer is a compiled Lisp function in `mh-buffers.el
'.
(mh-truncate-log-buffer)
If `mh-log-buffer' is too big then truncate it.
If the number of lines in `mh-log-buffer' exceeds
`mh-log-buffer-lines' then keep only the last
`mh-log-buffer-lines'. As a side effect the point is set to the
end of the log buffer.
The function returns the size of the final size of the log buffer.