Data records must follow all other records in the system file. There must be at least one data record in every system file.
The format of data records varies depending on whether the data is compressed. Regardless, the data is arranged in a series of 8-byte elements.
When data is not compressed,
each element corresponds to
the variable declared in the respective variable record (see Variable Record). Numeric values are given in
flt64 format; string
values are literal characters string, padded on the right when
necessary to fill out 8-byte units.
Compressed data is arranged in the following manner: the first 8 bytes in the data section is divided into a series of 1-byte command codes. These codes have meanings as described below:
biasfrom the file header. For example, code 105 with bias 100.0 (the normal value) indicates a numeric variable of value 5.
When the end of the an 8-byte group of command bytes is reached, any blocks of non-compressible values indicated by code 253 are skipped, and the next element of command bytes is read and interpreted, until the end of the file or a code with value 252 is reached.