[Info-vax] BACKUP, rsync, Time Machine (was: Re: Re; Spiralog, RMS Journaling...)

[Paul Sture]

On 2016-06-20, lawrencedo99 at gmail.com <lawrencedo99 at gmail.com> wrote:
> On Monday, June 20, 2016 at 5:39:08 PM UTC+12, Paul Sture wrote:
>> On 2016-06-20, Lawrence D’Oliveiro wrote:
>>> On Monday, June 20, 2016 at 2:47:43 AM UTC+12, Stephen Hoffman wrote:
>>>
>>>> rsync is somewhat analogous to Time Machine in that both copy files 
>>>> around.  But the two differ.  rsync is a remote synchronization tool.  
>>>> Time Machine is a backup tool, and maintains months or years of 
>>>> previous versions of files over one or more local or remote backup 
>>>> target volumes, as well as providing the ability to restore and boot 
>>>> the recovered volume(s), among other differences from rsync.  TM avoids 
>>>> storing duplicate copies of a file, though does not provide the file or 
>>>> sector-level de-dupling available with some storage systems.  Having 
>>>> used both, TM and rsync are different targets and different users and 
>>>> different implementations.
>>>
>>> rsync does all that and more.
>> 
>> Time Machine uses a File System Event store to track changed directories.
>
> rsync doesn’t need one.

Please explain.

-- 
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naming, and off-by-one errors.