zmq_curve_public - Man Page

derive the public key from a private key


int zmq_curve_public (char *z85_public_key, char *z85_secret_key);


The zmq_curve_public() function shall derive the public key from a private key. The caller provides two buffers, each at least 41 octets large. In z85_secret_key the caller shall provide the private key, and the function will store the public key in z85_public_key. The keys are encoded using zmq_z85_encode(3).

Return Value

The zmq_curve_public() function shall return 0 if successful, else it shall return -1 and set errno to one of the values defined below.



The libzmq library was not built with cryptographic support (libsodium).


Deriving the public key from a CURVE private key.

char public_key [41];
char secret_key [41];
int rc = zmq_curve_keypair (public_key, secret_key);
assert (rc == 0);
char derived_public[41];
rc = zmq_curve_public (derived_public, secret_key);
assert (rc == 0);
assert (!strcmp (derived_public, public_key));

See Also

zmq_z85_decode(3) zmq_z85_encode(3) zmq_curve_keypair(3) zmq_curve(7)


This page was written by the 0MQ community. To make a change please read the 0MQ Contribution Policy at

Referenced By

zmq(7), zmq_setsockopt(3), zmq_z85_decode(3), zmq_z85_encode(3).

08/13/2020 0MQ 4.3.3 0MQ Manual