gnutls_record_send_early_data — API function


#include <gnutls/gnutls.h>

ssize_t gnutls_record_send_early_data(gnutls_session_t session, const void * data, size_t data_size);


gnutls_session_t session

is a gnutls_session_t type.

const void * data

contains the data to send

size_t data_size

is the length of the data


This function can be used by a client to send data early in the handshake processes when resuming a session.  This is used to implement a zero-roundtrip (0-RTT) mode.  It has the same semantics as gnutls_record_send().

There may be a limit to the amount of data sent as early data.  Use gnutls_record_get_max_early_data_size() to check the limit.  If the limit exceeds, this function returns GNUTLS_E_RECORD_LIMIT_REACHED.


The number of bytes sent, or a negative error code.  The number of bytes sent might be less than  data_size .  The maximum number of bytes this function can send in a single call depends on the negotiated maximum record size.



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3.6.9 gnutls