We set the RFsim TCP socket to non-blocking. Thus, it may happen that we
cannot write() to the socket when the kernel cannot handle the request,
in which case we wait some time before trying again. This is the
correct/expected behavior.
Since this is *normal*, an error message is not justified; we did not
even print a message in this case before commit 21790f9c4f introduced it.
Robert Schmidt
09652061bb