Specifications

Section 2. Data Storage and Retrieval
2.4.4 TOB3 Binary File Format
The TOB3 binary format has a header similar to the other formats. TOB3 data
is stored in fixed size “frames” that generally contain a number of records.
The size of the frames is a function of the record size. The frames are time
stamped, allowing the calculation of time stamps for their records. If there is a
lapse in periodic interval records that does not occur on a frame boundary, an
additional time stamp is written within the frame and its occurrence noted in
the frame boundary. This additional time stamp takes up space that would
otherwise hold data.
When TOB3 files are converted to another format, the number of records may
be greater or less than the number requested in the data table declaration.
There are always at least two additional frames of data allocated. When the
file is converted these will result in additional records if no lapses occurred. If
more lapses occur than were anticipated, there may be fewer records in the file
than were allocated.
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