On Tue, 12 Sep 2006, Armel Asselin wrote:

>> Most protocols support HTTP proxy, but note that non-HTTP over such a proxy
>> will also speak HTTP unless you "tunnel through" it.

> I do not really understand what you mean by "non-HTTP over such a proxy will
> also speak HTTP"

It means that they will be convert into "GET [URL] HTTP/1.1" requests.

> I understand that tunneling is in fact connecting to the proxy, making a
> request to it to connect to the real target, then using the proxy connection
> 'as-if'. So without tunneling, does it mean that the FTP RETR would become a
> HTTP GET?

Yes.

> If I want to do full FTP (SIZE, RETR, MKDIR...) I must use tunneling, isn't
> it?

Yes. And most HTTP proxies are not setup to allow that.

>> Then there's socks4 and socks5 proxies and those are generally not very
>> well supported for anything, but I believe they work at least for plain
>> simple HTTP and probably for FTP too.

> hum it would be interesting to have a clear view of this (not really
> possible to explain to my users this kind of "it may or it may not"), if I
> can make a small table by digging in the code, i'll try to.

Feel free. I would also appreciate such a table. The SOCKS[45] code is in a
rather crappy state.

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