rsync with --copy-devices patch and device-target with --write-batch doesnt work

[freisei]

Matt McCutchen schrieb:
> On Fri, 2009-01-30 at 13:12 +0100, freisei wrote:
>   
>> i?ve found the problem.
>> "./rsync -v --copy-devices --progress 
>> --write-batch=/mnt/sdc1/snapshotvergleich/diff1 
>> /mnt/sdc1/snapshotvergleich/xp8main3-mnt-backup-base.img 
>> /dev/vg0/xp8main3-mnt-backup-1"
>> creates a diff1-file which has nearly the size of 
>> /mnt/sdc1/snapshotvergleich/xp8main3-mnt-backup-base.img because rsync 
>> with --copy-devices-param does not work as expected when a device is the 
>> target.
>>
>> So my filesystem was overfilled and "rsync error: error in file IO (code 
>> 11) at io.c(1565) [sender=3.1.0dev]" occured.
>>     
>
> OK, that explains that.
>
>   
>> My next question:
>>
>> Is it possible to tell rsync to treat a device-target lika a file?
>>     
>
> Not currently.  That's a separate feature from --copy-devices; it would
> be called --keep-devices, in analogy to --copy-dirlinks and
> --keep-dirlinks.
>
>   
Oh, OK.

i?ve done a look into the source, but my poor c abilities don?t allow to 
do it myself. I think that there is anyone other to do it, i?ve found 
another --keep-devices-post from 2006.

But, there would be another solution for me.

If i could create batch-files in "revert-mode" i can change source and 
destination.
Possible command-line:
rsync --write-batch=diff1.batch /dev/lvmvg1/current_snapshot 
/mnt/somewhere/oldsnapshot.img
Would even be better - after every run oldsnapshot.img is the current 
snapshot-image and diff
mv oldsnapshot.img currentsnapshot.img

Possible revert-command-line to get the snapshot from
rsync --read-revert-batch=diff1.batch /mnt/somewhere/currentsnapshot.img 
/mnt/somewhere/oldsnapshot.img

is there a wish-list for rsync to see how many users want to have which 
feature?

- Freisei