@deftypefun {int} {gnutls_ocsp_req_get_extension} (gnutls_ocsp_req_const_t @var{req}, unsigned @var{indx}, gnutls_datum_t * @var{oid}, unsigned int * @var{critical}, gnutls_datum_t * @var{data})
@var{req}: should contain a @code{gnutls_ocsp_req_t}  type

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

@var{oid}: will hold newly allocated buffer with OID of extension, may be NULL

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

@var{data}: will hold newly allocated buffer with extension data, may be NULL

This function will return all information about the requested
extension in the OCSP request.  The information returned is the
OID, the critical flag, and the data itself.  The extension OID
will be stored as a string.  Any of  @code{oid} ,  @code{critical} , and  @code{data} may
be NULL which means that the caller is not interested in getting
that information back.

The caller needs to deallocate memory by calling @code{gnutls_free()}  on
 @code{oid} ->data and  @code{data} ->data.

@strong{Returns:} On success, @code{GNUTLS_E_SUCCESS}  (0) is returned, otherwise a
negative error code is returned.  If you have reached the last
extension available @code{GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE}  will
be returned.
@end deftypefun