rsync silently changes special files to regular ones!

[jw schultz]

On Tue, Sep 16, 2003 at 12:12:04PM +0200, Paul Slootman wrote:
> On Fri 12 Sep 2003, jw schultz wrote:
> > > 
> > > i did:  "rsync localhost::rsync/readme /dev/stdout" given the hype
> > > "rsync(1) is an improved cp(1)" (which it is, no doubt about that)
> > 
> > I don't know where you got that idea.  You keep repeating it
> > despite its obvious incorrectness.  I certainly would not
> > describe rsync as an improved cp.  An improvement on rcp,
> > sure, but not an improved rcp either.  I see nothing in the
> > manpage or web site to indicate that its general behaviour
> > bears any equivalence to cp.
> 
> >From the manpage:
> 
>        You  can  also  use rsync in local-only mode, where both the source and
>        destination don´t have a ´:´ in the name. In this case it behaves  like
>        an improved copy command.
> 
> For me it's quite understandable that people then get the idea that
> "rsync(1) is an improved cp(1)".

I saw that line but couldn't make that extreme a conclusion.
That is jumping from analogy of a generic term to simile of
a specific.  I suppose it could do with a rewrite for those
for whom English is a second language.

Perhaps "When used in this way rsync behaves superficially
like a copy command"  or "This way rsync can be used for
a safer and in some cases more efficient file copying"
would be an improvement.

Aside from numerous other weaknesses that have crept into
the manpage i do note that there doesn't seem to be any
point where it is mentioned that rsync replaces destination
files rather than updating them in-place.  I'm not sure
where it would go in the current manpage.

I'm no writer but i have been toying with the idea of a
practical "how the rsync utility works for the
non-mathematician" document.  This wouldn't be a how-to but
would instead describe in broad terms what the rsync
internals are doing, the three processes involved and a
general sketch of the protocol.  Something that wouldn't be
obsoleted by enhancements.

-- 
________________________________________________________________
	J.W. Schultz            Pegasystems Technologies
	email address:		jw at pegasys.ws

		Remember Cernan and Schmitt