gnutls_dtls_set_data_mtu — API function


#include <gnutls/dtls.h>

int gnutls_dtls_set_data_mtu(gnutls_session_t session, unsigned int mtu);


gnutls_session_t session

is a gnutls_session_t type.

unsigned int mtu

The maximum unencrypted transfer unit of the session


This function will set the maximum size of the *unencrypted* records which will be sent over a DTLS session. It is equivalent to calculating the DTLS packet overhead with the current encryption parameters, and calling gnutls_dtls_set_mtu() with that value. In particular, this means that you may need to call this function again after any negotiation or renegotiation, in order to ensure that the MTU is still sufficient to account for the new protocol overhead.

In most cases you only need to call gnutls_dtls_set_mtu() with the maximum MTU of your transport layer.


GNUTLS_E_SUCCESS (0) on success, or a negative error code.



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3.6.9 gnutls