Re: A future for the SSH File Transfer Protocol?

[Jeffrey Altman <jaltman%columbia.edu@localhost>]

The reality is that a client should not have any idea what the
"realpath" means on the server.  This plus the notion of providing
access to uid/gid numbers is crazy when the world is not made up
entirely of Unix systems. 

How is FXP_REALPATH("~fred") different then GETHOME("fred") in regards
to how you are going to deal with it?


> Jeffrey Altman <jaltman%columbia.edu@localhost> wrote:
> 
> > Why should a client ever have to understand a system dependent alias
> > such as ~fred?
> > 
> > The only entity that should need to know how to map ~fred to what it
> > points to is the sender of the file.
> 
> Ah; you think it would be better for servers to understand `~fred'
> at the start of a pathname?
> 
> Fair enough, I suppose. But the rest of the ethos of SFTP seems to
> be that whatever alias or synonym you use to refer to a directory,
> you can always call FXP_REALPATH and get the full canonical name. So
> in my command-line SFTP client, I don't want to type `cd ~fred' and
> then have `pwd' just tell me `~fred'; I'd rather get the same
> behaviour I get at the real shell prompt, where I type `cd ~fred'
> and `pwd' tells me `/home/fred'.
> 
> I suppose that could be done just by making the server understand
> `~fred' at the start of a pathname, and then having the client call
> FXP_REALPATH("~fred") if it wanted the canonical form; but that
> starts to eat into the available characters in filenames, which is
> something SFTP has so far been scrupulous in not doing. So instead,
> my proposal was to introduce a protocol extension which allowed the
> client side to request the home directory of a particular user.
> 
> While I was at it, I also added name<->number mappings for users and
> groups, on the grounds that it seems silly that a command-line
> client can list the textual usernames of file owners by printing out
> the long name field, but a GUI client wanting to split all the
> details into separate columns has to make do with the numbers.
> 
> Cheers,
> Simon
> -- 
> Simon Tatham         "A cynic is a person who smells flowers and
> <anakin%pobox.com@localhost>    immediately looks around for a coffin."
> 



 Jeffrey Altman * Sr.Software Designer      C-Kermit 8.0 Beta available
 The Kermit Project @ Columbia University   includes Secure Telnet and FTP
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