Re: [ftpext] New Version of FTP HASH, RANG, LOCK, and HOST

"Alun Jones" <alun@texis.com> Sun, 27 January 2013 18:32 UTC

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From: "Alun Jones" <alun@texis.com>
To: =?iso-8859-1?Q?'=C1ngel_Gonz=E1lez'?= <keisial@gmail.com>, <bblackshaw@gmail.com>
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Date: Sun, 27 Jan 2013 10:32:39 -0800
Organization: Texas Imperial Software
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Cc: ftpext@ietf.org
Subject: Re: [ftpext] New Version of FTP HASH, RANG, LOCK, and HOST
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> Of Ángel González
> 
> Bruce Blackshaw wrote:
> > Re LOCK, I think it would be useful to have an alternative to
> > "boundary" called "size", that could provide the size of the raw data
> > for binary transfers.  That might provide quite a performance
> > advantage compared to having to search for the boundary.
> >
> > regards
> 
> Good point. I think it would be much more useful than the boundary
> method.
> The value of such size parameter should be the amount of data sent on the
> wire.

This has an obvious problem - what if the size of the file changes during
the transfer?

There are many uses of FTP (webcam being the one that comes immediately to
mind) where a "file" is retrieved, and is handled as if it is a
potentially-infinite stream. We have a webcam at work that encodes video as
an animated GIF that never ends. Doesn't display in Internet Explorer,
because IE is paranoid, but it's a use-case that should be considered. The
boundary method works for this use, where the size method doesn't.

Alun.
~~~~