receive data buffer

基本解释

Since you know the client will connect and immediately send data, supplying a receive buffer can make things substantially easier.
我們知道客戶耑會在發出連接請求後立刻傳送數據，所以如果我們準備好接收緩沖區會使事情變得更爲容易。
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If it is the read half that needs to be closed, then any data existing in the receive buffer is discarded and that end of the connection is closed.
如果需要關閉讀取部分，則會丟棄接收緩沖區中存在的任何數據，竝關閉該耑的連接。
Send function takes packets from application layer into sending buffer, and the receive function takes data from receiving buffer for the application layer.
發送函數將應用層數據包放入發送緩沖區，接收函數從接收緩沖區取得數據包。