18.104.22.168.3.2 Conformant Varying Strings
NDR64 represents a conformant varying string as an ordered sequence of representations of the string elements preceded by three unsigned 64-bit integers. The first 64-bit integer MUST specify the maximum number of elements in the string, including the terminator. The second 64-bit integer MUST specify the offset from the first index of the string to the first index of the actual subset being passed. The third 64-bit integer MUST specify the actual number of elements being passed, including the terminator.
The second 64-bit integer (offset) MUST be 0 (zero). See the following figure.
Figure 10: Conformant varying strings