From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Laight <David.Laight-ZS65k/vG3HxXrIkS9f7CXA@public.gmane.org>
Subject: RE: sysfs output without newlines
Date: Tue, 1 Sep 2020 09:07:42 +0000
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To: 'Joe Perches' <joe-6d6DIl74uiNBDgjK7y7TUQ@public.gmane.org>, Denis Efremov <efremov-vYTEC60ixJUAvxtiuMwx3w@public.gmane.org>, LKML <linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, Greg Kroah-Hartman <gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r@public.gmane.org>, "Rafael J. Wysocki" <rafael-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>, Kees Cook <keescook-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>, "Gustavo A . R . Silva" <gustavoars-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>, Julia Lawall <julia.lawall-MZpvjPyXg2s@public.gmane.org>, Alex Dewar <alex.dewar90-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Cc: York Sun <york.sun-3arQi8VN3Tc@public.gmane.org>, Borislav Petkov <bp-Gina5bIWoIWzQB+pC5nmwQ@public.gmane.org>, Mauro Carvalho Chehab <mchehab-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>, Tony Luck <tony.luck-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>, James Morse <james.morse-5wv7dgnIgG8@public.gmane.org>, Robert Richter <rric-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>, Michal Simek <michal.simek-gjFFaj9aHVfQT0dZR+AlfA@public.gmane.org>, Boris Brezillon <bbrezillon-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>, Maxim Levitsky <maximlevitsky-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, Alex Dubov <oakad-/E1597aS9LQAvxtiuMwx3w@public.gmane.org>, Ulf Hansson <ulf.hansson-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>, Tomas Winkler <tomas.winkler-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>, Arnd Bergmann <arnd-r2nGTMty4D4@public.gmane.org>, Madalin Bucur <madalin.bucur-3arQi8VN3Tc@public.gmane.org>, "David S. Miller" <davem-fT/PcQaiUtIeIZ0/mPfg9Q@public.gmane.org>, Jakub Kicinski <kuba-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>, Douglas Miller <dougmill-tEXmvtCZX7AybS5Ee8rs3A@public.gmane.org>, Stanislav Yakovlev <stas.yakovlev-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, Kalle Valo <kvalo-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org>, Darren Hart <dvhart-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>
List-Id: platform-driver-x86.vger.kernel.org

From: Joe Perches
> Sent: 29 August 2020 21:34
...
> > 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.

The shell will remove trailing '\n' (but not '\r') from:
	foo=$(cat bar)
So shell scripts are unlikely to be affected.

	David

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