gnutls_handshake

gnutls_handshake(3)                 gnutls                 gnutls_handshake(3)



NAME
       gnutls_handshake - API function

SYNOPSIS
       #include <gnutls/gnutls.h>

       int gnutls_handshake(gnutls_session_t session);

ARGUMENTS
       gnutls_session_t session
                   is a gnutls_session_t type.

DESCRIPTION
       This function does the handshake of the TLS/SSL protocol, and
       initializes the TLS connection.

       This function will fail if any problem is encountered, and will return
       a negative error code. In case of a client, if the client has asked to
       resume a session, but the server couldn't, then a full handshake will
       be performed.

       The non-fatal errors expected by this function are:
       GNUTLS_E_INTERRUPTED, GNUTLS_E_AGAIN, GNUTLS_E_WARNING_ALERT_RECEIVED,
       and GNUTLS_E_GOT_APPLICATION_DATA, the latter only in a case of
       rehandshake.

       The former two interrupt the handshake procedure due to the lower layer
       being interrupted, and the latter because of an alert that may be sent
       by a server (it is always a good idea to check any received alerts). On
       these errors call this function again, until it returns 0; cf.
       gnutls_record_get_direction() and gnutls_error_is_fatal(). In DTLS
       sessions the non-fatal error GNUTLS_E_LARGE_PACKET is also possible,
       and indicates that the MTU should be adjusted.

       If this function is called by a server after a rehandshake request then
       GNUTLS_E_GOT_APPLICATION_DATA or GNUTLS_E_WARNING_ALERT_RECEIVED may be
       returned.  Note that these are non fatal errors, only in the specific
       case of a rehandshake.  Their meaning is that the client rejected the
       rehandshake request or in the case of GNUTLS_E_GOT_APPLICATION_DATA it
       could also mean that some data were pending. A client may receive that
       error code if it initiates the handshake and the server doesn't agreed.

RETURNS
       GNUTLS_E_SUCCESS on success, otherwise a negative error code.

REPORTING BUGS
       Report bugs to <bugs@gnutls.org>.
       Home page: http://www.gnutls.org


COPYRIGHT
       Copyright © 2001-2016 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
       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

       http://www.gnutls.org/manual/

gnutls                               3.4.9                 gnutls_handshake(3)