[TAG] 2-cent Tip: Copying a partition

Kapil Hari Paranjape kapil at imsc.res.in
Tue Mar 20 17:43:07 MSK 2007


On Tue, 20 Mar 2007, Neil Youngman wrote:
> I'm not sure what this does that wouldn't be done by 'cp -ax'?

On Tue, 20 Mar 2007, Thomas Adam wrote:
> Note that the tar equivalent would be something like:
> 
> ```
> (tar cf - *) | ( cd /target; tar xfp -)
> '''

Plus the added dis-incentive that this "-x" switch is something handled
by libc rather than the kernel. This means:
	(0) There may be "hidden" directories that have been mounted over
	    which are seen by the "--bind" approach but are not seen
	    by the libc approach.
	(a) It may not work with "diet" libraries.
	(b) It may not work with "busybox" versions.
	(c) since it involves system calls it may be slower.
These assertions are untested but I believe (0) *must* logically be
true!

Regards,

Kapil.
--





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