>>I've been doing some conversions from RM Cobol, and it does have a weird data format. The index and data blocks are interspersed. I think I may still have some pieces of the converter I wrote, and it relies not on the structure being known, but on columns being recognized. From what I know about conversions from Cobol, the structure you may get is obsolete :). That's what happened to me each time I had it, and most of the time I didn't have it.
>
>Sounds like VSAM. http://sciris.shu.edu/Resources/Cs/c2113/c2113n10.htm

Exactly. I remember there were few blocks at the beginning, with no visible purpose, and I had to skip them just like the index blocks. RM85 seems to have its own variation of VSAM, because there's no variable length records, and the size of the block is actually size of the record, plus some 6 or 8 bytes overhead. This could mean that the structure of the indexes may have been weird for some narrow tables with relatively long index expressions.

Anyway, that can't be too bad, if it's still in use after so many years :)