Determine if there is Data left on the socket and discard it

Question

I\'m writing an Interface under Linux which gets Data from a TCP socket. The user provides a Buffer in which the received Data is stored. If the provided Buffer is to small

Answer 1

There is no knowledge at TCP level about what constitutes an application protocol message. There are, however, two most common ways to delimit messages in a TCP stream:

• prefix messages with their size and read that many bytes, or
• read till a certain sequence of bytes is found.

In this light, a generic TCP reader should provide two reading functions to be universally useful:

• to read N bytes, and
• to read till a delimiter has been read

A design similar to Tornado IOStream reading functions would do.