On Fri, 7 Dec 2007, Jeff Vincent wrote:

> However, the packet trace still doesn't show the complete 226/QUIT/221
> sequence.

That's probably the manifestation of the bug/problem.

> Where can we look, set breakpoints, what CURL options to set conditions we
> can poll for? The initial thought was that if we can watch for the 226
> ourselves, we can then know it's safe to clean up.

You could start with setting a breakpoint in Curl_ftp_done() since that is
called for the DONE action, which is immediately after a transfer has
completed (good or bad). That function should wait for the 226 and return fine
when things are fine.

But I would also urge you to continue your search for problems on either
7.17.1 or even the bleeding CVS code so that we know you're not suffering from
an old artifact of some kind.

> Does curl use separate threads to process responses from the server?

No. It uses no threads at all, except for the name resolving (and then it uses
threads only on Windows not on other platforms).

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