I want to encrypt the SQLite database in my QT application. This tutorial: http://www.qtcentre.org/wiki/index.php?title=Building_QSQLITE_driver_with_AES-256_encryption_support seems promising. But I know QT is licensed under LGPL (and I'm not allowed to purchase a commercial license due to some reason) and LGPL has some restrictions against code modification. Can I: 1) follow the tutorial; 2) use the modified QT with LGPL; 3) keep my application close-sourced?
You would have to redistribute your modified QtSql library, and so you would have to distribute the complete, machine compilable source code necessary to build that library.
Your modified library would remain LGPL which means you would have the same rights/responsibilities using it as you would if you used the standard Qt distributed one.
This means that if your application's current usage of the Qt library is permissible under the LGPL, then using the modified library in the same way is also permissible.
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