taglinefilesource code
TCP_LAST_ACK750net/inet/af_inet.ccase TCP_LAST_ACK:
TCP_LAST_ACK2269net/inet/tcp.cns=TCP_LAST_ACK;
TCP_LAST_ACK2422net/inet/tcp.csk->state == TCP_LAST_ACK ||
TCP_LAST_ACK3573net/inet/tcp.cif (sk->state == TCP_LAST_ACK) 
TCP_LAST_ACK3776net/inet/tcp.ctcp_set_state(sk,TCP_LAST_ACK);
TCP_LAST_ACK4918net/inet/tcp.csk->state != TCP_LAST_ACK &&