The only way to do a two-party transaction between untrusted peers (an implementation of BIP38)
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An intermediate code allows the other party to generate an encrypted private key based on your passphrase without them actually knowing the passphrase.
Typically the person receiving the coins is the person to generate the intermediate code.
Generate the encrypted private key using the intermediate code that you were given by the other party.
You will lose access to the coins unless the other party provides you with the passphrase to the encrypted private key.
Use your original passphrase and the confirmation code provided by the other party to verify that the address generated was based on your passphrase.
Once verified, the other party can send coins to the address. You will not have access to the coins until the other party sends you the encrypted private key.
Decrypt an encrypted private key using a passphrase.
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