2.2.3.2.3 Generating Stream Name

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The third step in creating the property name to property ID mapping stream is to use the stream ID to generate a hexadecimal identifier. The hexadecimal identifier is a ULONG ([MS-DTYP]) and is generated in this case by setting the first 16 bits to be the stream ID and the last 16 bits to be 0x0102. The computation of the hexadecimal identifier is as follows:

 Hexadecimal Identifier = (stream ID << 16) | 0x00000102

The stream name is then generated by prefixing the hexadecimal identifier with the following string: "__substg1.0_". For example, if the stream ID is 0x100A, the hexadecimal identifier is 0x100A0102 and the stream name is "__substg1.0_100A0102".

Multiple named properties can be mapped to the same stream if the same stream ID is generated by the stream ID equation.