@deftypefun {int} {gnutls_x509_rdn_get_oid} (const gnutls_datum_t * @var{idn}, unsigned @var{indx}, void * @var{buf}, size_t * @var{buf_size})
@var{idn}: should contain a DER encoded RDN sequence

@var{indx}: Indicates which OID to return. Use 0 for the first one.

@var{buf}: a pointer to a structure to hold the peer's name OID

@var{buf_size}: holds the size of  @code{buf} 

This function will return the specified Object identifier, of the
RDN sequence.

@strong{Returns:} On success, @code{GNUTLS_E_SUCCESS}  (0) is returned, or
@code{GNUTLS_E_SHORT_MEMORY_BUFFER}  is returned and * @code{buf_size} is
updated if the provided buffer is not long enough, otherwise a
negative error value.

@strong{Since:} 2.4.0
@end deftypefun