As long as the connections are from the same machine (local filesystem), it's fine.
Reads are concurrent, writes block reads (and other writes) while they write. (There's also something called WAL mode that enables reads during a write, which uses multiple files for each database.)
Reads are concurrent, writes block reads (and other writes) while they write. (There's also something called WAL mode that enables reads during a write, which uses multiple files for each database.)