What’s the proper way to impose a packet scheme on a stream protocol like TCP?
The two most common methods are delimiters and length-prefixing. An example of delimiters is separating packets with, say, a caret (^). Naturally your delimiter must never occur in regular data, or you must have some way of “escaping” delimiter characters. An example of length-prefixing is prepending a two-byte integer containing the packet length on every packet. See the FAQ article How to Use TCP Effectively for the proper way to send integers over the network. Also see the How to Packetize a TCP Stream example. There are hybrid methods, too. The HTTP protocol, for example, separates header lines with CRLF pairs (a kind of delimiting), but when an HTTP reply contains a block of binary data, the sever also sends the Content-length header before it sends the data, which is a kind of length-prefixing. I favor simple length-prefixing, because as soon as you read the length prefix, you know how many more bytes to expect. By contrast, delimiters require that you blindly read until you find
