mh-mark-active-p

mh-mark-active-p is an autoloaded Lisp macro in `mh-acros.el'.

(mh-mark-active-p CHECK-TRANSIENT-MARK-MODE-FLAG)

A macro that expands into appropriate code in XEmacs and nil in GNU Emacs.
In GNU Emacs if CHECK-TRANSIENT-MARK-MODE-FLAG is non-nil then
check if variable `transient-mark-mode' is active.