Index format 2 will not handle all > 2 GB files

[edwardhartnett]

Unfortunately, based on a conversation with @webisu I have learned that further modifications are required for index format 2 to work on all large GRIB2 files.

Large GRIB2 files will have sections < 2 GB. But since they can be 2 GB, indexes to a section within a message must be 8-byte ints. Currently we use 4-byte ints. We need to change to 8 byte ints.

[edwardhartnett]

@AlysonStahl-NOAA and @AlexanderRichert-NOAA this will be a problem for tocgrib2 as well.

[edwardhartnett]

OK, this has been a ton of work, but the index file now uses 8-byte ints everywhere that it should.

The only thing left for this issue is to inspect the code for cases where I still use 4-byte ints internally. All these values need to be 8-byte everywhere in the code.