diff --git a/doc/efun/exec b/doc/efun/exec
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+SYNOPSIS
+        int exec(object new, object old)
+
+DESCRIPTION
+        exec() switches the connection from the interactive object old
+        to the object new. If the new object is also interactive, it's
+        connection will be transferred to the old object, thus
+        exchaning the two connections between the object. If the new
+        object is not interactive, the old will not be interactive
+        anymore after the exec call succeeded.
+
+        The result is 1 on success, and 0 on failure.
+
+        exec() is used to load different "user objects" or to reconnect
+        link dead users.
+
+        To provide security mechanisms, the interpreter calls
+        master->valid_exec(current_program, new, old), which must
+        return anything other than 0 to allow this exec() invocation.
+
+        After the exec(), if arg 2 was this_player(), this_player()
+        becomes arg 1, else vice versa. Ditto for this_interactive().
+
+        Take care when writing a simul-efun around exec(): the
+        'current_program' passed to the valid_exec() function will be
+        that of the simul-efun object. To get around this, use
+        bind_lambda() to bind #'exec to the real object and funcall()
+        the resulting closure.
+
+EXAMPLE
+        ob = clone_object("std/player");
+        exec(ob, this_object());
+        destruct(this_object());
+
+HISTORY
+        LDMud 3.2.9 added the switchover of this_interactive().
+
+SEE ALSO
+        connect(M), disconnect(M), logon(A), interactive(E)