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FRM Files

Constant size = 1990 bytes (RBSIZ_FILE)
Offsets are 1-based, not 0-based
Little-endian format
Rather good description at http://www.clicketyclick.dk/databases/xbase/format/frm.html up to the “data structures” part
Other info from the source of the public domain DBE package at http://www.the-oasis.net/ftpmaster.php3?content=ftputils.htm
Differences noted with above reference
- Files start and end with “02 00”. They don't end with the array of data structures

Remove 1 from all offsets, due to xBase using 1-based offsets
01-02 Version = 02 00
03-04 Offset: RBOFF_EXPSIZE = 3, Size: 2, contents: d2 00 = 210 (DBE: nExpSize)
05-114 Offset: RBOFF_LENGTHS = 5, Size: RBSIZ_LENGTHS = 110, contents: 55 expression length values (DBE: cLengths)
115-224 Offset: RBOFF_OFFSETS = 115, Size: RBSIZ_OFFSETS = 110, contents: 55 expression offset values (DBE: cOffsets)
225-1664 Offset: RBOFF_EXPRS = 225, Size: RBSIZ_EXPRS = 1440, contents: 55 expression values (DBE: cExprs)
1665-1964 Offset: RBOFF_FIELDS = 1665, Size: RBOFF_SIZE = 300, contents: n report fields (DBE: cFields). Different from the xbase info.
1965-1988 Offset: RBOFF_PARAMS = 1965, Size: RBSIZ_PARAMS = 24, contents: report parameters ?. Different from the xbase info.
1989-1990 Version = 02 00

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