The &cw(new_vlevel) value must be one of the following constants which have the
indicated meanings:
+&indent
&beg_dlist(1i : &bold_font )
&ditem(RMR_VL_OFF)
Turns off all message writing. This includes the stats and debugging messages generated by the
route collector thread which are normally affected only by the externally managed verbose
level file (and related environment variable).
-&half_space
&ditem(RMR_VL_CRIT)
Write only messages of critical importance.
Debugging must have also been enabled during the build as a precaution to accidentally
enabling this level of output as it can grossly affect performance.
&end_dlist
+&uindent
&space
Generally RMR does not write messages to the standard error device from &ital(critical path)