VMS Help RMS, $TRUNCATE  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    The Truncate service shortens a sequential file.

                         RAB64 USERS (ALPHA ONLY)

       On Alpha systems, RAB64 can replace the RAB or RAB prefix
       wherever it is used with the Truncate service on OpenVMS
       Alpha systems.

    Format

      SYS$TRUNCATE  rab [,[err] [,suc]]

  Additional Information (explode) :

• Returns
• Arguments
• Condition Values Returned