RE: [PATCH 4/4] lib/hexdump.c: Allow multiple groups to be separated by lines '|'

["Alastair D'Silva" <alastair@d-silva.org>]

> -----Original Message-----
> From: David Laight <David.Laight@ACULAB.COM>
> Sent: Wednesday, 10 April 2019 6:45 PM
> To: 'Alastair D'Silva' <alastair@au1.ibm.com>; alastair@d-silva.org
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> Subject: RE: [PATCH 4/4] lib/hexdump.c: Allow multiple groups to be
> separated by lines '|'
> 
> From: Alastair D'Silva
> > Sent: 10 April 2019 04:17
> > With the wider display format, it can become hard to identify how many
> > bytes into the line you are looking at.
> >
> > The patch adds new flags to hex_dump_to_buffer() and
> print_hex_dump()
> > to print vertical lines to separate every N groups of bytes.
> >
> > eg.
> > buf:00000000: 454d414e 43415053|4e495f45 00584544
> NAMESPAC|E_INDEX.
> > buf:00000010: 00000000 00000002|00000000 00000000  ........|........
> 
> Ugg, that is just horrid.
> It is enough to add an extra space if you really need the columns to be more
> easily counted.
>

I did consider that, but it would be a more invasive change, as the buffer length required would differ based on the flags.
 
> I'm not even sure that is needed if you are printing 32bit words.
> OTOH 32bit words makes 64bit values really stupid on LE systems.
> Bytes with extra spaces every 4 bytes is the format I prefer even for long
> lines.
> 
> Oh, and if you are using hexdump() a lot you want a version that never uses
> snprintf().
> 
> 	David
> 
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