udp.md•1.06 kB
# UDP 使用示例
<!-- verify -->
```cangjie
import std.net.*
import std.sync.*
let SERVER_PORT: UInt16 = 33333
let barrier = Barrier(2)
func runUdpServer() {
try (serverSocket = UdpSocket(bindAt: SERVER_PORT)) {
serverSocket.bind()
barrier.wait()
let buf = Array<Byte>(3, repeat: 0)
let (clientAddr, count) = serverSocket.receiveFrom(buf)
let sender = (clientAddr as IPSocketAddress)?.address.toString() ?? ""
// Server receive 3 bytes: [1, 2, 3] from 127.0.0.1
println("Server receive ${count} bytes: ${buf} from ${sender}")
}
}
main(): Int64 {
let fut = spawn {
runUdpServer()
}
barrier.wait()
try (udpSocket = UdpSocket(bindAt: 0)) { // random port
udpSocket.sendTimeout = Duration.second * 2
udpSocket.bind()
udpSocket.sendTo(
IPSocketAddress("127.0.0.1", SERVER_PORT),
[1, 2, 3]
)
}
fut.get()
return 0
}
```
运行结果：
```text
Server receive 3 bytes: [1, 2, 3] from 127.0.0.1
```