taglinefilesource code
keepopen183include/net/sock.hkeepopen,
keepopen190net/core/sock.csk->keepopen = valbool;
keepopen271net/core/sock.cval = sk->keepopen;
keepopen892net/ipv4/tcp.cif (sk->keepopen)
keepopen1711net/ipv4/tcp.csk->keepopen = 1;
keepopen952net/ipv4/tcp_input.c} else if (sk->keepopen) {
keepopen1118net/ipv4/tcp_input.cif (sk->keepopen) 
keepopen814net/ipv4/tcp_output.cif(sk->keepopen)