TH_ECN
#ifndef TH_ECN
TH_ECN, TH_CWR };
TH_ACK, TH_URG, TH_ECN, TH_CWR };
if (tcp->th_flags & TH_ECN)
#ifndef TH_ECN
{ TH_ECN, 'E' },
if ((tcpflags & ~(TH_ECN|TH_CWR)) == TH_SYN) {
} else if ((tcpflags & ~(TH_ECN|TH_CWR)) ==
TH_ECN|TH_CWR)
#ifndef TH_ECN
#define TH_ECNALL (TH_ECN|TH_CWR)