@deftypefun {int} {gnutls_x509_crq_get_extension_info} (gnutls_x509_crq_t @var{crq}, unsigned @var{indx}, void * @var{oid}, size_t * @var{sizeof_oid}, unsigned int * @var{critical})
@var{crq}: should contain a @code{gnutls_x509_crq_t}  type

@var{indx}: Specifies which extension number to get. Use (0) to get the first one.

@var{oid}: a pointer to store the OID

@var{sizeof_oid}: initially holds the maximum size of  @code{oid} , on return
holds actual size of  @code{oid} .

@var{critical}: output variable with critical flag, may be NULL.

This function will return the requested extension OID in the
certificate, and the critical flag for it.  The extension OID will
be stored as a string in the provided buffer.  Use
@code{gnutls_x509_crq_get_extension_data()}  to extract the data.

If the buffer provided is not long enough to hold the output, then
* @code{sizeof_oid} is updated and @code{GNUTLS_E_SHORT_MEMORY_BUFFER}  will be
returned.

@strong{Returns:} On success, @code{GNUTLS_E_SUCCESS}  (0) is returned, otherwise a
negative error code in case of an error.  If your have reached the
last extension available @code{GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE} 
will be returned.

@strong{Since:} 2.8.0
@end deftypefun