Firebird Pascal API Guide

And related Firebird Pascal API package (fbintf)

The fbintf package provides the Firebird API in a format where all data types for SQL data, interface parameters and results are native Pascal types, including all parameter blocks and database information. The Pascal API is pitched at a similar level and purpose to the IBPP Firebird API provided to the C++ world. The package is intended to be suitable for use on any platform supported by the Free Pascal Compile, and Delphi Win32.

https://www.mwasoftware.co.uk/fb-pascal-api