Re: Question around of remote description

[Leland Best]

Eric, et al,

On Wed, 2020-06-17 at 08:26 +0100, Mike Fleetwood wrote:
> On Wed, 17 Jun 2020 at 07:16, Eric L. Zolf <ewl+rdiffbackup@lavar.de>
> wrote:
> > Hi,
> > 
> > in the course of the review of PR #404 we came to challenge the
> > quite
> > complex quoting rules allowed when you backup to/from a remote
> > location.
> > 
> > Our question is if anybody is relying on those (too) complex
> > quoting
> > rules to make their backup work? Else it'll allow us to radically
> > simplify the code.
> > 
> > More details: if you backup to/from a remote site, the description
> > is of
> > the form `host::path` (e.g. `rdiff-backup /home
> > myuser@myhost::/srv/backup/homebak`), and the current quoting
> > allows to
> > have the double colons (::) somewhere in the `host` or `path` part
> > of
> > the remote description. And the question is if anybody knows of a
> > concrete use case for this possibility?
> > 
> > For even more gory details, the man page states the quoting rules
> > in the
> > REMOTE OPERATION section.
> > 
> > Thanks, Eric
> > 
> > PS: and yes, double colons are a valid POSIX path part (`touch ::`
> > works), but who really needs it?
> > 
> > https://github.com/rdiff-backup/rdiff-backup/pull/404
> 
> It looks like colon is not a valid character in a host name so that
> shouldn't be used anywhere.

Not in the hostname, no.  But colons _do_ occur in file names.  As a
concrete example, on a recent Linux box '/sys/bus/pci/devices' contains
symbolic links named like '000:00:00.0'.  So, when I do a "full system
backup" I may well have filenames with colons.

> 
> https://stackoverflow.com/questions/3523028/valid-characters-of-a-hostname
> https://en.wikipedia.org/wiki/Hostname
> 

Cheers
Leland
-- 
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Leland C. Best      | Creationists make it sound as though a 'theory' is
lcbpublic@gmail.com | something you dreamt up after being drunk all night.
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