VMS Help MMS, Description File, Macros  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    A macro is a name that represents a character string.  You can define
    a  macro  at  the  beginning  of  the  description file or on the MMS
    command line and then use its name anywhere in the  description  file
    in  place  of  the equivalent string.  A macro must be defined before
    you use it.

    Format:

      name = string

    The name identifies the macro,  and  the  string  is  the  text  that
    replaces  the  name  when  the macro is expanded.  A macro definition
    must begin in column 1 of the line.  To invoke a macro, type:

         $(name)

    You can define a macro on the command line with the /MACRO qualifier;
    you can also use a CLI symbol as a macro.

    If a macro is not defined in the description file, MMS looks  in  its
    environment for macro definitions.  To find them, it looks at symbols
    defined by the CLI assignment  statement,  scanning  the  CLI  symbol
    table  for the body of the macro.  If the body of the macro is not in
    the  CLI  symbol  table,  MMS  substitutes  a  null  string  for  all
    invocations of the macro.

    MMS supplies some default, or "built-in," macro definitions and  some
    "special" macros for use in action lines.