bug#7362: dd strangeness

[Pádraig Brady]

On 01/03/11 17:45, Paul Eggert wrote:
> On 03/01/2011 03:27 AM, Pádraig Brady wrote:
> 
>> So the standard way to accumulate short reads to a full write,
>> is to specify separate ibs and obs (we'd probably want to prompt about
>> setting obs too for efficiency)
> 
> Yes, good point, the diagnostic should suggest ibs=N obs=N
> (instead of just ibs=N).
> 
> By the way, the relationship between fullblock and ibs=N obs=N is
> a curious one, one that I don't fully understand.  If you have
> ibs=N obs=N, why would you need fullblock?  This should probably
> be documented (preferably by someone who understands it :-).

Well as I understand it, it's to do with 'count'.
count refers to the number of input reads,
both partial and full.

So the advice to use iflag=fullblock is probably safer,
especially when a count (or skip) is specified.

cheers,
Pádraig.