The Messages package provides a way to retrieve messages stored in a
  file separate from your program. It consists of a single class, Messages.
  Objects of this class retrieve the text of messages for a given
  message set number.

  A message set number is an OpenVMS message identification code, including
  a facility code (bits 16 through 27) and a facility-specific bit (bit 15);
  all other bits should be 0. To process the message file, use the OpenVMS
  Message Utility (see the OpenVMS Message Utility Manual for details).
  Link the resulting object code into one of the following:

 	Your program
 	A shareable image that your program is linked against
 	A shareable image that is then specified with the set message
 	command

  Header:

 	#include <messages.hxx>