You're asking about locking in the source file, right?
So when you import to File1.fmp12 to File2.fmp12, will the records in File2.fmp12 be locked at any point?
The answer is no. Import will not lock the source records and therefore it doesn't matter if they are locked by another user. The last committed values will be imported.
You buried the answer at the end. So actively locked records will be sent as source data with the last committed data. Interesting. I will test that.
Well you say source file but reference File2?
So actively locked records will be sent as source data with the last committed data. Interesting. I will test that.
That makes total sense when you think about it. If a client exports, FMS will need to send it all the data. FMS is aware of locked records but not about the uncommitted data. Only the client with the record open knows what the uncommitted data is. The server only knows what the committed data is.
This is the same principle that I used a few years ago for my audit log devcon session: At the moment of commit (and the OnCommit is a pre-event trigger) you can get both the old and new data, saving you from having to store all the old data ahead of time.
Your FMP client will know the new data, you can ask FMS through PSoS for the old data since FMS has not received the new data yet.