The facilities described below implement the VMS logical name system using
the EMAS profile scheme.  On EMAS the logical names are only significant for
the first 11 characters (cf.127 on VMS).  All the strings are converted to
upper case before they are stored or translated.

!< ASSIGN

   ASSIGN <text>,<log-name>

   This assigns the string <text> to the logical name <log-name>.
   If the parameters are omitted then they are prompted for.
   The message 'Previous logical name assignment replaced' is given if the
   logical name was defined before it was re-set.

   eg.  ASSIGN TTYPE=11,VISUAL200

!>
!< DEASSIGN

   DEASSIGN <log-name>

   The logical name specified is deleted.  The message 'No logical name match'
   is given if the logical name is not defined.

   eg.   DEASSIGN VISUAL200
!>
!< SEE

   SEE <log-name>

   This can be used to look at the value of a logical name.

   eg.  SEE VISUAL200
        Log-name VISUAL200 => TTYPE=11
!>
!< TRANSLATE

   %external %string (255) %fn %spec TRANSLATE (%string (255) LNAME)

   This returns the translation of the logical name specified as its parameter
   as its result.  If the logical name was not defined then the logical name
   is given as a result.

   eg.       %if TRANSLATE("DEFAULTDEV")#"DEFAULTDEV" %start
                 ! Do something with the external default
             %else
                 ! Cope with the program default
             %finish
!>