socket.getSendBufferSize()

• 返回：<number> SO_SNDBUF 套接字发送缓冲区大小（以字节为单位）。

  ¥Returns: <number> the SO_SNDBUF socket send buffer size in bytes.

如果在未绑定的套接字上调用此方法将抛出 ERR_SOCKET_BUFFER_SIZE。

¥This method throws ERR_SOCKET_BUFFER_SIZE if called on an unbound socket.