title: Will read() ever block after select()?
body: <p>I'm reading a stream of data through TCP/IP socket. The stream load is very uneven. Sometimes large bulks of data arrive every second, sometimes no data come for an hour. In the case of long inactivity period (no data from remote server, but connection is still online) my program should take some actions.</p>
  
  <p>I'm implementing a timeout using a select(). It tells me if there are data ready, but I don't know exactly how much can I read without causing read() to block. Blocking is unacceptable as it may last far longer than the timeout I need.</p>
  
  <p>For the sake of efficiency, stream is read into large buffer and read() call is provided with that buffer size.</p>
  
  <p>Will read() block after select() if the buffer to be filled is greater than amount of data available right now in the socket? </p>