 Each text unit consists of a two byte "text unit key" identifying this text unit, a two-byte big-endian binary number of length-data pairs that follow for this key (usually one), a two byte length field identifying the length of the text unit data, and a text unit of the specified length.Implementations are expected to ignore any text unit information not relevant to the receiving system.Header Control Record
The header record must be the first record of a NETDATA file.