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

    The Open service makes an existing file available for processing
    by your program. The Open service specifies the type of record
    access to be used and determines whether the file can be shared.
    The Open service also performs an implicit Display service.

    Format

      SYS$OPEN  fab [,[err] [,suc]]

  Additional Information (explode) :

• Returns
• Arguments
• Condition Values Returned