Re: Last stream problem: byte order

[Stephen Leake <stephen.a.leake.1@gsfc.nasa.gov>]

Erik Sigra <sigra@home.se> writes:

> Now my stream application almost works. The last remaining problem
> seems to be byte order. The server is programmed in C++ with Qt and
> the client is programmed in Ada with adasockets-1.0. The last thing
> I did was to change the byte order in the server
> ("the_stream.setByteOrder(QDataStream::LittleEndian);"). After that
> the numbers came out right at the other end.
> 
> However, this may not be a safe solution. The safe way would probably be to 
> always have the network communication in BigEndian format and make sure the 
> client always obeys this, regardless of the platform.
> 
> So how does one set the byte order to BigEndian on the Ada side? 

By writing code that does it :). There is a package Word_Order_Convert
in SAL at http://users.erols.com/leakstan/Stephe/Ada/sal.html

Note that's _word_ order convert; you'll need _byte_ order convert.
Should be easy to change. I was working with 1553 buses, which are all
16 bit words.

> Or is there a different, better idea?

You can use a higher layer communications package, that does byte
swapping for you. There is one called XDR in the GNAT GLADE
distributed annex package.

-- 
-- Stephe