cURL / Mailing Lists / curl-library / Single Mail


RE: FTP keep alive connection

From: Patrick Monnerat <>
Date: Mon, 5 Nov 2007 22:09:42 +0100

Patrick Monnerat wrote:

> Right: the NOOP command must be supported. But the handling of the
> connection while a data transfer is active is not well defined: this
> the real potential problem. Light servers have the "permission" to
> the control connection while transfering data. In that case, the
> mechanism defined in RFC959 seems a bit hazardous...

In addition, sending a NOOP to the server implies we should expect a 200
response that is not handled at all by the current patch. When a data
transfer is active, this response may come before or worse: even AFTER
the data transfer completion response, because the server may have
started to send the later while we are sending the NOOP :-(
As a consequence, the handling of this asynchronous command/response
exchange does not seem as simple as it first looks.
Received on 2007-11-05