What is the function of the RST hole?

[VonAshley]

The RST on the car is a reset button that can restore the navigation system to factory settings. It is usually not a port but a small hole. When the system crashes or needs to be restored to factory settings, use an object similar to a toothpick to extend into the small hole and touch the switch. After restarting, the factory settings can be restored. Additional information is as follows: 1. Common situations for generating a reset: When a connection request arrives, there is no process listening on the target port. For UDP, when a datagram reaches the destination port and the port is not in use, it will generate an ICMP port unreachable message, while TCP uses a reset. 2. There are two advantages for an application to abnormally terminate a connection: Discard any pending data and immediately send a reset segment; the receiver of the RST will distinguish whether the other end performed an abnormal close or a normal close. The API used by the application must provide a means to generate an abnormal close rather than a normal close.