在通过TCP / SSL套接字发送内容之前发送/接收文件名

I have the servers connected, but I don't really understand how TCP works well enough to accomplish the task. I want to send the file name before I starting writing the content, but how can I read the file name separately from the content. This was really easy in UDP with socket.receive(packet), but I can't think of a comparable way of doing this with TCP sockets.I have the servers connected, but I don't reall