gnutls_session_get_id(3)             gnutls             gnutls_session_get_id(3)

       gnutls_session_get_id - API function

       #include <gnutls/gnutls.h>

       int gnutls_session_get_id(gnutls_session_t session, void * session_id,
       size_t * session_id_size);

       gnutls_session_t session
                   is a gnutls_session_t type.

       void * session_id
                   is a pointer to space to hold the session id.

       size_t * session_id_size
                   initially should contain the maximum  session_id size and
                   will be updated.

       Returns the TLS session identifier. The session ID is selected by the
       server, and in older versions of TLS was a unique identifier shared
       between client and server which was persistent across resumption.  In the
       latest version of TLS (1.3) or TLS with session tickets, the notion of
       session identifiers is undefined and cannot be relied for uniquely
       identifying sessions across client and server.

       In client side this function returns the identifier returned by the
       server, and cannot be assumed to have any relation to session resumption.
       In server side this function is guaranteed to return a persistent
       identifier of the session since GnuTLS 3.6.4, which may not necessarily
       map into the TLS session ID value. Prior to that version the value could
       only be considered a persistent identifier, under TLS1.2 or earlier and
       when no session tickets were in use.

       The session identifier value returned is always less than

       On success, GNUTLS_E_SUCCESS (0) is returned, otherwise an error code is

       Report bugs to <>.
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gnutls                               3.6.13             gnutls_session_get_id(3)