Date: Mon, 23 Jan 2017 23:10:51 +0100 From: Jilles Tjoelker <jilles@stack.nl> To: "Simon J. Gerraty" <sjg@juniper.net> Cc: Lu Tung-Pin <lutungpin@openmailbox.org>, freebsd-current@freebsd.org, des@freebsd.org Subject: Re: Fix /etc/rc.d/random umask handling (/entropy permissions) Message-ID: <20170123221050.GA77550@stack.nl> In-Reply-To: <43886.1485197541@kaos.jnpr.net> References: <14f5a2fdf191c33e4ed1dc882b288e81@openmailbox.org> <20170121220136.GA59654@stack.nl> <43886.1485197541@kaos.jnpr.net>
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On Mon, Jan 23, 2017 at 10:52:21AM -0800, Simon J. Gerraty wrote:
> Jilles Tjoelker <jilles@stack.nl> wrote:
> > Index: etc/rc.d/random
> > ===================================================================
> > --- etc/rc.d/random (revision 311446)
> > +++ etc/rc.d/random (working copy)
> > @@ -20,12 +20,14 @@
> >
> > save_dev_random()
> > {
> > + oumask=`umask`
> why not simply use a sub-shell to tighten umask
> (umask 077; what-ever)
With our /bin/sh, the save-restore method saves a fork. A command
substitution with a single umask command does not fork, while a subshell
containing umask and something else does.
The effect is fairly minor, but good performance is often the product of
many small optimizations.
--
Jilles Tjoelker
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