Re: [PATCH 1/5] vsprintf/Documentation: Add X to %*ph extension to output upper case hex

[Andy Shevchenko]

On Thu, Aug 26, 2021 at 11:43:01AM -0700, Joe Perches wrote:
> A few sysfs output uses of hex arrays are uppercase and are nominally ABI.
> 
> Add a mechanism to the existing vsprintf %*ph hex output extension to
> support upper case hex output.

...

> +	The preferred output is lowercase
>  	%*ph	00 01 02  ...  3f
>  	%*phC	00:01:02: ... :3f
>  	%*phD	00-01-02- ... -3f
>  	%*phN	000102 ... 3f
> +	Formats with X are uppercase, used for backwards compatibility
> +	%*phX	00 01 02  ...  3F
> +	%*phCX	00:01:02: ... :3F
> +	%*phDX	00-01-02- ... -3F
> +	%*phNX	000102 ... 3F

Why not using %*pH...?

...

> +	char locase = 0x20;	/* ASCII OR'd for lower case see: number() */

If you use h vs H, you may derive this from (fmt[...] & SMALL).

-- 
With Best Regards,
Andy Shevchenko