Re: dd conv=nocache

[Jim Meyering]

Pádraig Brady <address@hidden> wrote:
> I was thinking it would be useful to
> add an option to dd to tell it to
> instruct the OS not to cache the data.

I like the idea, even if it works only with very recent Linux
kernels.

> Personally I use dd to move large files like disc images etc.
> around, and I know I will not need the file cached.
>
> A very quick example patch which has only
> been tested on linux is attached.
>
> Do you think this is required?
> Do you think this is the right interface?

There are two separate sets of data to which we
might want to apply such an optimization: input and output.

So how about an interface that lets the user disable caching on
either or both?  E.g., no-i-cache no-o-cache.
I find the "-"-less options far less readable.
Actually, I prefer the even longer names:
  input-cache-disable
  output-cache-disable

nocache could still be an alias for the combination.