Re: dd in loop doesn't transfer full blocks

Henrik Carlqvist <[email protected]> Wed, 06 Oct 2010 20:47:45 +0200
Newsgroups gmane.comp.gnu.utils
Organization SunSITE.dk - Supporting Open source
Message-ID <[email protected]>
jim <[email protected]> wrote:

> On Oct 6, 2:37 am, Henrik Carlqvist <[email protected]>
>> Is $BS a multiple of something? If so, maybe it would help to do something
>> like:
>>
>> do  dd bs=`echo $BS/8 | bc` count=8
 
> but I really want a method that doesn't depend
> on my guessing correctly a number (8 in your example) that _might_
> make the problem go away, but also might not.

I can't say for sure of the problem is because of the block size being
bigger than some buffer size you will have to try to see if it works.

However if you don't want to guess on a number, pick the safe number: 1

do  dd bs=1 count=$BS

It will probably give some performance penalty, but hopefully it will
still be good enough for your purpose.

regards Henrik
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