Subject RE: [ib-support] How to decide when a new secondary file is required
Author Leyne, Sean
> How to detect whether Firebird is using only the first file.
> Or is it using the second, third fourth secondary files etc.

You need to investigate the system tables RDB$PAGES and RDB$FILES (See
Language Reference -- System Tables and Views), to determine if the
system has allocated a page in a secondary file.