It supports multiple readers, and writes are atomic - no reader should ever get corrupt data just because there is a write happening in parallel. You probably should not use the OS to copy the live db file, rather, have an in-process thread that reads the db and writes to a backup location periodically.

Exactly, many forget the little detail that they should use the backup feature, rather than just copy the database file.

You can also combine file system snapshots to get versioning which would allow you to pull the db file out of the latest snapshot (right after taking it) and send it somewhere