Hello, I have a question:
Suppose I send out a bitcoin transaction without fee from wallet 1 to wallet 2, and from wallet 2 to 3.
Now If I double spend these bitcoins the transaction from 1 to 2 'never happened' and the same holds for the transaction from 2 to 3.
But what if the transaction from 1 to 2 is not confirmed (yet) (no fee), but the transaction from 2 to 3 is using a fee and is already confirmed.
Is the first transaction then automatically confirmed? And can't the 1st transaction be double spend anymore?
The point is that you cannot double spend. That's the whole point of bitcoin. So no, there's no "automatic confirmation", and no, it's not possible to double spend.
I know you cannot really double spend a bitcoin.
what I mean is if I send out the same bitcoin twice, once without fee, the other with fee.
It is very likely the one with fee is confirmed and the other transaction therefore never happened.
but if I send a transaction without fee, and the reciever sends out the funds immediately with fee, that transaction could be confirmed, but not (yet) the deposit.