coolfluid/coolfluid3 — comment on commit 0095488da18a46ddaa2c90416a761e18f8612554
File: cf3/ui/server/ServerNetworkComm.cpp line 125
By barche:

OK. I also found a thread and a bug about this:
http://www.qtcentre.org/threads/29462-QTcpSocket-sends-data-twice-with-flush()

Also, I had added debugging comments inside the send() function before
each write (in the loop and in the else), and verified with wireshark
that one call to QTcpSocket::write generated TWO signalframes on the
wire. When flush is gone this does not happen. I suspect some sort of
race condition (inside QT) between the controlling thread handling the
writing, and the call to flush.