/sys$common/syshlp/helplib.hlb PASCAL, /ENUMERATION_SIZE=keyword D=platform-specific  *Conan The Librarian (sorry for the slow response - running on an old VAX)

 Controls the allocation of unpacked  enumerated  data  types  and
 Boolean data types, which are considered to be an enumerated type
 containing   two   elements.    Note    that    specifying    the
 ENUMERATION_SIZE  attribute  overrides  any  value you previously
 specified with this qulaifier.

 You can specify the following values for keyword:

    BYTE
      Allocates unpacked enumerated data types with fewer than 255
      elements in a 8-bit byte. Otherwise, the enumerated type is
      allocated in a 16-bit word.  Default on OpenVMS VAX systems.

    LONG
      Allocates all unpacked enumerated types in a 32-bit longword.
      Default on OpenVMS Alpha systems.