VMS Help TCPIP Services, Programming Interfaces, RPC XDR Routines, xdr_bytes, Arguments  *Conan The Librarian (sorry for the slow response - running on an old VAX)

 xdrs
    A pointer to an XDR stream handle created by one of the XDR
    stream handle creation routines.
 bpp
    A pointer to a pointer to the byte array.
 sizep
    A pointer to the length of the byte array.
 maxsize
    The maximum size of the length of the byte array.