help on packet format for tcp/ip programming

[Grant Edwards]

On 2007-02-08, Diez B. Roggisch <deets at nospam.web.de> wrote:

>>>> struct module pack and unpack will only work for fixed size buffer :
>>>> pack('>1024sIL', buffer, count. offset) but the buffer size can vary
>>>> from one packet to the next  :-(
>>>
>>> Oh for Pete's sake...
>>>
>>> struct.pack('>%dsIL' % len(buffer), buffer, count, offset)
>>
>> 
>> that is great but how does one unpack on the other side?
>
> By peeking into the header, determining the number of bytes necessary?

Better yet, use a protocol that's not brain-dead: send the
buffer size _before_ you send the buffer.

> But why do you need this anyway - if you know that you will
> have python on both ends, use Pyro or xmlrpc.

-- 
Grant Edwards                   grante             Yow!  A dwarf is passing
                                  at               out somewhere in Detroit!
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