Question

I’m porting a windows network application to linux and faced a timeout problem with select call on linux. The following function blocks for the entire timeout value and returns while I checked with a packet sniffer that client has already sent the data.

int recvTimeOutTCP( SOCKET socket, long sec, long usec )
{
  struct timeval timeout;
  fd_set fds;.

  timeout.tv_sec = sec;
  timeout.tv_usec = usec;
  FD_ZERO( &fds );
  FD_SET( socket, &fds );

  // Possible return values:
  // -1: error occurred
  // 0: timed out
  // > 0: data ready to be read
  cerr << "Waiting on fd " << socket << endl;
  return select(1, &fds, 0, 0, &timeout);
}

Answer 1

I think the first parameter to select() should be socket+1.

You really should use another name as socket also is used for other things. Usually sock is used.