> I thought it was about 2GB/4GB - depending on what you read and where?

2GB limit does hols for interbase ans some variants of FB 1.0 only. FB
1.5 does use 64Bit Fileaccess which does allow larger files.

> What is the single file size limit on FAT32, NTFS Linux, etc?

FAT32 is limited to 2 GB, for NTFS and Linux this limit is removed in
current versions - both do have old versions with that limitation.

Elmar