1 if the point was successfully hashed. 0 will cause secp256k1_ecdh to fail and return 0. Other return values are not allowed, and the behaviour of secp256k1_ecdh is undefined for other return values. Out: output: pointer to an array to be filled by the function In: x32: pointer to a 32-byte x coordinate y32: pointer to a 32-byte y coordinate data: arbitrary data pointer that is passed through
A pointer to a function that hashes an EC point to obtain an ECDH secret