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From: Don G (dongryphon_at_[hidden])
Date: 2005-04-24 18:32:54


Hi Peter,

>>> This of course leads to the obvious question:
>>> which network gives me a stream over COM1?
>>
>> network_ptr com1 =
>> new net_over_stream(
>> new stream_over_serial("com1"));
>
> Wait a minute. Which network creates the
> stream_over_serial? Assume that I don't need
> the outer network since I'll be communicating
> with a printer, for example.

Serves me right for being glib. :)

Here's what I meant:

  class stream_over_serial : public net::stream
  {
   public:
     stream_over_serial (string comport);
  };

This is a net::stream impl over the named COM device. On Windows,
this might use lineOpen.

Now that we have a stream, we wrap it in a network:

  class network_over_stream : public net::network
  {
   public:
     network_over_stream (net::stream_ptr strm);
  };

The caller of all this is whom so ever wanted a network running over
the COM port. (glib again, I know<g> but this is just a sketch).

FWIW: We use host names like "g" and "h" for "guest" and "host" where
the "guest" is the initiator/active open and "host" is the
acceptor/passive open. The new_local_address() would return "g" as a
physical address on the side that did the above.

> My point was that different network objects can
> interpret the same address to mean different
> things, at least in theory. URIs are supposed to
> be context-independent.

I see your point. Your suggestion of encoding the network as part of
the URI would solve this. That could be a global map/table or a
multi-net impl of net::network (one that was a net::network and
wrapped a collection of network's; not that I want to go there<g>).
But, these schemes would still compete with the set defined for the
Internet (the http:// form should work since it is universal).

The issue was that I wanted user visible addresses to be familiar
(such as the now infamous "http://www.boost.org"). Given that desire,
and the fact that our most heavily used network impl was TCP/IP, I
had no problem with this level of abuse. ;)

Also, the same protocol can run over multiple nets, so "foo://G" or
"foo://10.0.0.7" just made some (twisted<g>) sense to me and I never
worried about the ambiguity.

Do you see this as an acceptable abuse, or as doing violence to the
RFC? :)

Best,
Don

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