Re: [Bug-ddrescue] ddrescue 10x slow under osx

[Antonio Diaz Diaz]

Hola Florian,

Florian Sedivy wrote:
> Given that - judging from the participants of the mailing list - 
> approximately half of ddrescue's users are on OS X,

Or maybe OS X users need more help than other users. ;-)


> The big question is: where would be the right spot for this
> information, if you want to keep even the documentation strictly
> OS-agnostic?

I'll add some of this information to the ddrescue manual (for example 
that raw character devices may have a defined size). But, given that 
most of the information is not specific to ddrescue but to accessing 
discs on OS X, I guess the right spot for it would be some OS X site or 
forum.


> Then (if that method is generic enough) it could be inserted as an
> alternative to the O_DIRECT flag for platforms where that is unsupported.

If I ever discover a method for direct disc access more generic than 
O_DIRECT, I'll probably implement it instead of (not as an alternative 
to) O_DIRECT. I hate arbitrary differences among systems, and I work to 
reduce their number.


> Something else: cat is quite a generic command, and still it manages 
> to somehow select the optimal Copy Block Size for a raw character 
> device on OS X. If the relevant code is not platform specific, it 
> might contain some nice ideas.

If it is the cat from GNU coreutils, it probably includes platform 
specific code for every system under the sun through gnulib. But I'll 
look at the code just in case. :-)


Regards,
Antonio.