On 13/05/10 11:42, Karel Zak wrote:
> On Thu, May 13, 2010 at 10:35:47AM +0100, Pádraig Brady wrote:
>> On 13/05/10 09:31, Karel Zak wrote:
>>>
>>> The blklimits program is the command-line interface to working with
>>> I/O topology support in the libblkid library. For example:
>>>
>>> # blklimits /dev/sdb
>>> alignment offset: 0
>>> minimum io size: 4096
>>> optimal io size: 32768
>>> logical sector size: 512
>>> physical sector size: 4096
>>
>> Could you mention why you chose to have a separate command
>> rather than adding extra options to `blockdev`?
>
> Good point.
>
> The blockdev already supports topology ioctls, but libblkid provides
> more portable API. The ioctls are supported since kernel 2.6.32, and
> the stuff is exported by /sys since 2.6.31. The libblkid is able to
> read the information directly from DM, MD, LVM and EVMS on older
> kernels. The library provides unified API for all these probing
> methods and we need any command-line interface for this functionality
> (for fdisk/parted, mkfs debugging etc.).
Thanks for that info.
>
> I'm not sure if link blockdev(8) against libblkid is a good idea.
> From my point of view is blockdev(8) simple wrapper for ioctls.
>
> (I'm not happy with another new command, so suggestions are welcomed.)
blockdev currently just uses ioctls but I don't see a problem
linking with libblkid if available and {add,merg}ing the new
options if so.
So in summary I would change the blockdev description from:
"blockdev - call block device ioctls from the command line"
to:
"blockdev - query or change block device parameters"
cheers,
Pádraig.
--
To unsubscribe from this list: send the line "unsubscribe util-linux-ng" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
