Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!munnari.oz.au!metro!seagoon.newcastle.edu.au!cc.newcastle.edu.au!sysnet
From: sysnet@cc.newcastle.edu.au
Newsgroups: comp.archives.admin
Subject: Re: New version of my ftpd is now available
Message-ID: <1991Jun18.144427.10268@cc.newcastle.edu.au>
Date: 18 Jun 91 04:44:27 GMT
References: <3661@sirius.ucs.adelaide.edu.au> <1991Jun16.092611.15695@newshost.anu.edu.au>
Followup-To: comp.archives.admin
Organization: University of Newcastle, AUSTRALIA
Lines: 35

In article <1991Jun16.092611.15695@newshost.anu.edu.au>, cmf851@anu.oz.au (Albert Langer) writes:
> The CHANGE file in ftpd.5.60.tar.Z mentions that with the new version of
> ftpd for BSD systems, ftp can no longer directly run ls.
> 
> I have been working on some software (originally by Tony Moraes,
> supplied by Ed Vielmetti) which relies on using ls -alR to obtain a
> recursive directory listing. (I believe it could be used to greatly reduce
> internet traffic, especially at peak times and on international links.
> Cheap unix 386 boxes or very cheap Coherent unix lookalikes could 
> provide a "transparent" cache/relay service.) Should I assume 
> that ftp use of ls -alR will soon be broken on most BSD systems?

I think assuming ls -alR will work on everything is fraught with danger.

A couple of months ago, I spent some time trying to set up a mirror of a 
number of files in different anonymous ftp areas.  After looking at a couple 
of existing things, I found none to be satisfactory, so began looking at how 
to do it myself.

One of the things I tried was ls -alR to find out what was there.  It turned 
out that only a little over half of the sites I wanted would return something 
useful.  And when you think about it, anything that does not use ls will 
generally not understand ls -alR.  This now obviously includes a lot of unix 
machines, but also includes all the non-unix machines.  It is not a universal 
solution which makes is not terribly useful.

A slightly relevent digression in case anyone is interested:
The files I wanted to mirror were just selected files or subdirectories from a
number of machines.  I did not want to mirror entire archives as most of the 
existing things did.  It would be nice if anyone thinking about 
mirroring/caching software could take this into account.
-- 
David Morrison, Manager, Networks and Comms, Uni of Newcastle, Australia
sysnet@cc.newcastle.edu.au or (VAX PSI) psi%0505249626002::sysnet
Phone: +61 49 215397	Fax: +61 49 216910