TCP_IW_MAXSEGS_DFLT
if (tcp_iw_maxsegs < TCP_IW_MAXSEGS_DFLT)
tcp_iw_maxsegs = TCP_IW_MAXSEGS_DFLT;
rt->rt_rmx.rmx_iwmaxsegs < TCP_IW_MAXSEGS_DFLT ||
static u_long tcp_iw_maxsegs = TCP_IW_MAXSEGS_DFLT;