[dm-devel] [PATCH] Add human-readable units modifier to vsnprintf()

[Kent Overstreet]

On Tue, May 22, 2012 at 10:42:40PM -0700, Joe Perches wrote:
> > Yeah, I already ran into that. I was looking through the gcc docs to see
> > if there was a way to add modifiers (how is it done for the other kernel
> > specific format strings?) but I haven't found anything yet
> 
> It's done via %p extensions.
> gcc doesn't care as long as the %p argument is a pointer.

Ahh

> 
> > > It's also possible
> > > to confuse it with printf's own 'h' / 
> > > integer precision use.
> > 
> > Well, that's annoying. Any suggestions?
> 
> I gave you one already.

Missed the reason for your suggestion :)

> 
> Use a new lib/vsprintf.c %p pointer extension like 
> "%pD" or "%pH" and use a pointer to the type as the
> argument.

Only trouble is we lose the existing method of specifying the type of
the integer. New flag character would make much more sense... if gcc
could be persuaded.