TCPOPT_SACK_PERMIT_HDR 4252 netinet/tcp_input.c *((u_int32_t *)optp) = htonl(TCPOPT_SACK_PERMIT_HDR); TCPOPT_SACK_PERMIT_HDR 566 netinet/tcp_output.c htonl(TCPOPT_SACK_PERMIT_HDR);