@deftypefun {int} {gnutls_x509_ext_export_basic_constraints} (unsigned int @var{ca}, int @var{pathlen}, gnutls_datum_t * @var{ext})
@var{ca}: non-zero for a CA

@var{pathlen}: The path length constraint (set to -1 for no constraint)

@var{ext}: The DER-encoded extension data; must be freed using @code{gnutls_free()} .

This function will convert the parameters provided to a basic constraints
DER encoded extension (2.5.29.19).
The  @code{ext} data 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