[Q] About block/nonblock TCP Sending in ns2

[he@expert.cc.purdue.edu]

Gurus:
	Hi, I'm wondering whether the current implementation
of TCP application sending  function is in block mode or 
unblocked mode. Say, if I do a "send" in TcpApp of ns2,
can I expect this call will be blocked until the sending
of the message accomplished or the function call will
return immediately as an asynchronous send in socket?
If it was the latter case (unblocked), then how could I
find out the queue length of the underlying Tcp protocol
so that in the application could I know whether I could
inject more data to the TCP or not.
	Thank you very much.


Kaichuan