scp not tolerant of extraneous shell messages

[Bryan Henderson]

>Perhaps scp could have a special -diagnose option which runs 'echo
>hello' at the remote end, and checks that the text received is just
>'hello'.  That would save unfortunate users a lot of headscratching in
>future. 

That would certainly be a nice thing to do for the users -- though actually
harder to do than just making scp act like the terminal emulator download
program that it is and just ignore junk before the protocol starts.

A middle ground -- not changing the function of scp, but reducing the 
diagnosis time when people run into this -- is just to fix the error message
scp issues when it gets unexpected garbage from the other side.  Today, the
message is the garbage itself.  Attaching a few words of explanation would
do wonders.  Also, add more narrative to the -v output.  In my own debugging
effort, I ended up adding several useful messages.

>Of course, this is really a suggestion for the rcp program since scp
>is just rcp-over-SSH.

Again, I'm confused about the connection.  I know scp aims to
substitute for rcp, but do they actually share code?  Would an
enhancement to scp have to go into rcp too for engineering purposes?

-- 
Bryan Henderson                                    Phone 408-621-2000
San Jose, California