@deftypefun {int} {gnutls_x509_ext_export_name_constraints} (gnutls_x509_name_constraints_t @var{nc}, gnutls_datum_t * @var{ext}) @var{nc}: The nameconstraints @var{ext}: The DER-encoded extension data; must be freed using @code{gnutls_free()} . This function will convert the provided name constraints type to a DER-encoded PKIX NameConstraints (2.5.29.30) extension. The output data in @code{ext} will be allocated using @code{gnutls_malloc()} . @strong{Returns:} On success, @code{GNUTLS_E_SUCCESS} (0) is returned, otherwise a negative error value. @strong{Since:} 3.3.0 @end deftypefun