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Subject: Re: sysfs output without newlines
From:   Joe Perches <joe@perches.com>
To:     Denis Efremov <efremov@linux.com>,
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Date:   Sat, 29 Aug 2020 13:33:56 -0700
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On Sat, 2020-08-29 at 23:23 +0300, Denis Efremov wrote:
> Hi,
> 
> On 8/29/20 9:23 PM, Joe Perches wrote:
> > While doing an investigation for a possible treewide conversion of
> > sysfs output using sprintf/snprintf/scnprintf, I discovered
> > several instances of sysfs output without terminating newlines.
> > 
> > It seems likely all of these should have newline terminations
> > or have the \n\r termination changed to a single newline.
> 
> I think that it could break badly written scripts in rare cases.

Maybe.

Is sysfs output a nominally unchangeable api like seq_?
Dunno.  seq_ output is extended all the time.

I think whitespace isn't generally considered part of
sscanf type input content awareness.

> > Anyone have any objection to patches adding newlines to these
> > in their original forms using sprintf/snprintf/scnprintf?
> 
> I'm not sure about existing cases, but I think it's a good
> checkpatch.pl warning for new patches. It should be 
> possible to check sysfs_emit() calls.

Eventually, yes.

cheers, Joe