gnutls_session_get_id(3) — Linux manual page


gnutls_session_get_id(3)         gnutls         gnutls_session_get_id(3)

NAME         top

       gnutls_session_get_id - API function

SYNOPSIS         top

       #include <gnutls/gnutls.h>

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

ARGUMENTS         top

       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.

DESCRIPTION         top

       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

RETURNS         top

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

REPORTING BUGS         top

       Report bugs to <>.
       Home page:

COPYRIGHT         top

       Copyright © 2001- Free Software Foundation, Inc., and others.
       Copying and distribution of this file, with or without
       modification, are permitted in any medium without royalty
       provided the copyright notice and this notice are preserved.

SEE ALSO         top

       The full documentation for gnutls is maintained as a Texinfo
       manual.  If the /usr/share/doc/gnutls/ directory does not contain
       the HTML form visit 

COLOPHON         top

       This page is part of the GnuTLS (GnuTLS Transport Layer Security
       Library) project.  Information about the project can be found at
       ⟨⟩.  If you have a bug report for this
       manual page, send it to  This page was obtained
       from the tarball gnutls-3.7.8.tar.xz fetched from
       ⟨⟩ on 2022-12-17.  If you
       discover any rendering problems in this HTML version of the page,
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gnutls                            3.7.8         gnutls_session_get_id(3)