Re: version 2.2 --remove-older-than behavior changed

On 17.02.2023 09:06, Eric Zolf wrote:
> Hi,
>
> On 17/02/2023 07:02, [email protected] wrote:
>> I really appreciate rdiff-backup and like the new command syntax, so 
>> I don't want to sound like a whiner, but like tbsky the change to 
>> make "No increment is older than ...." a warning and return a nonzero 
>> status code disruptive and a big surprise.
>
> I agree, this is why it has been documented in the changelog with the 
> prefix CHG, which exactly means "review this and act accordingly 
> before you update".
> And I _always_ write in the release notes "Detailed release notes are 
> at the top of the changelog. As always, consider especially the 
> changes marked with CHG as they might impact your workflow." but who 
> reads release notes properly? :-^
>
>> I, and I imagine many others, run "rdiff-backup remove increments 
>> --older-than ..." before every backup.  For backups containing slowly 
>> changing files, it reports "No increment is older than ...." most of 
>> the time.  I would guess that in all my different backups I get "No 
>> increment is older than ...." about 1/3 of the time.  I'm happy to 
>> see the "NOTE: No increments older than ... found, exiting." message, 
>> but I see no reason for an additional WARNING that just clutters the 
>> output of my backup script making it more difficult to notice when 
>> there a real problems, and especially a nonzero status code that will 
>> cause my script to terminate unless I change the shell setting to 
>> ignore errors, which means the script won't terminate when there is a 
>> "real" problem.
>
> That isn't correct, the script will need to be changed, true, but you 
> can use something like:
>
> rdiff-backup <do something>
> rc = $?
> if [[ $(( rc ^ (2+4+8) & rc )) -gt 0 ]]; then echo error; fi
>
> and hence ignore anything which isn't an error (return codes 2, 4 and 
> 8 are warnings, and they can be combined; search for "bitwise" in the 
> bash manpage for details).
>
> _and_ you can do something else with the return code, which you 
> couldn't do before, like reporting warnings with a lower severity in 
> your monitoring system. In the past, a return code != 0 could mean 
> anything, now I'm trying to sort this out properly, so that people can 
> rely on it to take decisions, trigger monitoring, whatever. There is 
> still a lot more to be done to reach this state of bliss, but Rome 
> wasn't built in one day. 

Getting complicated. I agree, that "No increment is older than 20D" 
shouldn't be a warning, it's quite normal behaviour.

Good luck
Reio