The structural append feature allows up to 16 symbols in a structure. A capable reader can either buffer the contents of each symbol until all symbols are read, or deliver the data chunk by chunk.
To encode structural append, you must provide three settings for each symbol:
Symbol Sequence Indicator (SI). The sequence indicator is 1-based index which identify the position of this particular symbol in the group. Can be any number between 1 and 16.
Total number of symbols (TS). This value indicates the number of total symbols. Can be any number between 1 and 16. The value should be consistent among all symbols in the group.
File Identification Number(FID). Identify the symbol group. This number must remain the same among all the symbols in the group.
The tilde codes sequence is expressed in the following format:
~2[SI][FID][TS]
For example, tilde code sequence ~2[1][126][6]
indicates
that the current symbol belongs to a group with file identification
number as 126, and there are 6 symbols in total in this group.
The ~2 tilde code sequence must appear at the end of the input. All three fields are required and must be enclosed with square brackets ([ and ]) and must follow the tilde code ~2.
The File ID is a number remaining constant among all symbols in a group. It uniquely identifies the symbol group. The value for this field should be between 1 and 64516.
Sequence indicator is a 1-based index number of the current symbol. In a group with total 10 symbols, the first symbol has the SI as 1 and the last has the SI as 10.