I notice that when issuing an scp command at the client side, on the
server side (at least for OpenSSH) a command is sent to do the copy. This
is another scp command, which seems to take options not listed in the scp
man pages.

Anybody know where to find a description of the scp commands sent to
the server when a client attempts an scp transfer to or from it?

Frank W. Steiner <steinfw@hotmail.com> writes:
>Anybody know where to find a description of the scp commands sent to
>the server when a client attempts an scp transfer to or from it?

The source code of an 'scp' implementation.

I'm not aware of any document describing the protocol.

On Mon, 11 Sep 2006 22:20:13 +0100, Jacob Nevins wrote:

> Frank W. Steiner <steinfw@hotmail.com> writes:
>>Anybody know where to find a description of the scp commands sent to the
>>server when a client attempts an scp transfer to or from it?
>
> The source code of an 'scp' implementation.
>
> I'm not aware of any document describing the protocol.

Hmm... How do different implementations manage to interoperate? Did they
all "copy" an original implementation? Which one was it?

>>>>> "FWS" == Frank W Steiner <steinfw@hotmail.com> writes:

FWS> On Mon, 11 Sep 2006 22:20:13 +0100, Jacob Nevins wrote:
>> Frank W. Steiner <steinfw@hotmail.com> writes:
>>> Anybody know where to find a description of the scp commands sent
>>> to the server when a client attempts an scp transfer to or from
>>> it?
>> The source code of an 'scp' implementation.
>>
>> I'm not aware of any document describing the protocol.

FWS> Hmm... How do different implementations manage to
FWS> interoperate?

They interoperate because the protocol is exceedingly simple.

--
Richard Silverman
res@qoxp.net

On Tue, 12 Sep 2006 00:30:30 -0400, Richard E. Silverman wrote:

>>>>>> "FWS" == Frank W Steiner <steinfw@hotmail.com> writes:
>
> FWS> On Mon, 11 Sep 2006 22:20:13 +0100, Jacob Nevins wrote:
> >> Frank W. Steiner <steinfw@hotmail.com> writes:
> >>> Anybody know where to find a description of the scp commands sent
> >>> to the server when a client attempts an scp transfer to or from
> >>> it?
> >> The source code of an 'scp' implementation.
> >>
> >> I'm not aware of any document describing the protocol.
>
> FWS> Hmm... How do different implementations manage to FWS>
> interoperate?
>
> They interoperate because the protocol is exceedingly simple.

But if there is no written specification then some particular
implementation of scp must be the reference one, right? Which one is it?

Frank W. Steiner <steinfw@hotmail.com> writes:
>But if there is no written specification then some particular
>implementation of scp must be the reference one, right? Which one is it?

There's no particular reason why everyone should have chosen the same
"reference implementation" to reverse-engineer their SCP implementations
from.

I suspect that the de facto "reference implementation" will probably
turn out to be Ylonen et al's original ssh (which I think invented SCP),
or its derivative OpenSSH, simply because the source is widely
available.

On Wed, 13 Sep 2006 00:16:15 +0100, Jacob Nevins wrote:

> Frank W. Steiner <steinfw@hotmail.com> writes:
>>But if there is no written specification then some particular
>>implementation of scp must be the reference one, right? Which one is it?
>
> There's no particular reason why everyone should have chosen the same
> "reference implementation" to reverse-engineer their SCP implementations
> from.
>
> I suspect that the de facto "reference implementation" will probably turn
> out to be Ylonen et al's original ssh (which I think invented SCP), or its
> derivative OpenSSH, simply because the source is widely available.

OK, thanks.