RPCL Opaque Data

Opaque data is used in XDR to describe untyped data, that is, sequences of arbitrary bytes. You can declare opaque data either as a fixed-length or variable-length array.

Examples:

opaque diskblock[512]; --> char diskblock[512];
opaque filedata<1024>; --> struct {
                             u_int filedata_len;
                             char *filedata_val;
                         } filedata;