@deftypefun {size_t} {gnutls_record_check_pending} (gnutls_session_t @var{session}) @var{session}: is a @code{gnutls_session_t} type. This function checks if there are unread data in the gnutls buffers. If the return value is non-zero the next call to @code{gnutls_record_recv()} is guaranteed not to block. @strong{Returns:} Returns the size of the data or zero. @end deftypefun