VMS Help RTL Routines, SMG$, SMG$ERASE_PASTEBOARD, Argument  *Conan The Librarian (sorry for the slow response - running on an old VAX)

 pasteboard-id

    OpenVMS usage:identifier
    type:         longword (unsigned)
    access:       read only
    mechanism:    by reference

    Specifies the pasteboard to be erased. The pasteboard-id
    argument is the address of an unsigned longword that contains
    the pasteboard identifier.

    The pasteboard identifier is returned by SMG$CREATE_PASTEBOARD.