What's your favourite SFTP client?

[ewx]

I've been writing an SFTP server. It's not complete but it is good enough to start testing against a wider variety of clients.

So what other SFTP clients should I test against? I'm disinclined to pay money merely to test interoperability but don't mind looking at free-as-in-beer clients; obviously free software clients are better in that I can look inside and see why they're doing things. I've got Windows XP, OS X and Linux and home and can get access to several other UNIX platforms.

The list so far.

If you're brave enough to try out incomplete, undocumented and scantily tested software, then see this page for instructions. It runs on OS X and Linux, though at any given point one or the other might be temporarily broken.

Why is it better than the OpenSSH server? It supports SFTP protocol versions up to 6 (although some of the v6 support isn't done yet), which implies support for filename encoding translating, text mode transfers, string chown/chgrp, sub-second timestamps, hard links and extra rename semantics.

As part of the process I've summarized information about SFTP protocol version differences here.

Comments

[fanf]

Does it address the small-window performance problem?

[ewx.livejournal.com]

What problem did you have in mind? It can cope with clients stacking up multiple read/write requests without waiting for responses, if that's what you mean.

[fanf]

http://www.cs.auckland.ac.nz/~pgut001/pubs/app_sec.pdf p.20

[ewx.livejournal.com]

That appears to be an SSH design flaw that can be exacerbated by sufficiently poor choices in SFTP clients. My program is neither an SSH implementation nor an SFTP client, so I'm not sure what I'm supposed to do about it.

(It does include an SFTP client, in fact, but that is intended for testing only, and doesn't get installed.)