TCP state
Represents the states of a TCP connection
The native macOS IP connection exposes TcpState?. TCP sockets use the entries below, with UNKNOWN for an unrecognized native state. Non-TCP sockets return null; the native mapper does not return NONE.
Entries
| State | Description |
|---|---|
| UNKNOWN | The native TCP state is not recognized |
| CLOSED | The TCP connection is closed |
| LISTEN | The socket is listening for incoming connection requests |
| SYN_SENT | A connection request has been sent |
| SYN_RECV | A connection request has been received and establishment is in progress |
| ESTABLISHED | The connection is established and can transfer data |
| FIN_WAIT_1 | A request to close the connection has been sent |
| FIN_WAIT_2 | The peer has acknowledged the request to close the connection |
| CLOSE_WAIT | The peer has requested closure and the local side has not yet closed |
| CLOSING | Both sides are closing the connection |
| LAST_ACK | The local side is waiting for acknowledgment of its final close request |
| TIME_WAIT | The connection is waiting before completing closure |
| NONE | A placeholder for the absence of a valid TCP state |