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What does a socket state TIME_WAIT, that can be seen in command like netstat, mean?

$ netstat -tulpan
Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program name
tcp        0      0         TIME_WAIT   -

TCP guarantees the reliability by sending back Acknowledgment (ACK) packets back for a single or a range of packets received from the peer. This goes same for the control signals such as termination request/response. RFC 793 defines the TIME-WAIT state to be as follows:

TIME-WAIT - represents waiting for enough time to pass to be sure the remote TCP received the acknowledgment of its connection termination request.