CONFIG_C_FFI invert [IF]
  cr
  ." To run this program on Gforth 0.7.3 we need the C FFI, as setsockopt" cr
  ." is not available in 0.7.3." cr
  abort
[THEN]

\ Gforth 0.7.3 doesn't seem to have these defined.
     2 Constant AF_INET
   $40 Constant MSG_DONTWAIT
 $4000 constant MSG_NOSIGNAL
  2048 constant SOCK_NONBLOCK
     1 constant SOL_SOCKET
     2 Constant SO_REUSEADDR
    11 constant EAGAIN

sockaddr_in nip constant /sockaddr_in
4               constant /option_value

' closesocket alias close

c-library socketextlib
  c-function setsockopt setsockopt n n n a n -- n ( sockfd level optname optval optlen -- r )
end-c-library