title: Zero Window when sending files through posix sockets
body: <p>I have a problem - when I'm trying to send huge amounts of data through posix sockets ( doesn't matter if it's files or some data ) at some point I don't receive what I expect - I used wireshark to determine what's causing errors, and I found out, that exactly at the point my app breaks there are packets marked red saying "zero window" or "window full" sent in both directions.</p>
  
  <p>The result is, that the application layer does not get a piece of data sent by send() function. It gets the next part though...</p>
  
  <p>Am I doing something wrong?</p>
  
  <p>EDIT: </p>
  
  <p>Lets say I want to send 19232 pieces of data 1024 bytes each - at some random point ( or not at all ) instead of the 9344th packet I get the 9345th. And I didn't implement any retransmission protocol because I thought TCP does it for me.</p>