RFC: Adding a hw.features[2] sysctl

[Igor Mozolevsky]

On 14/01/2008, Daniel O'Connor <doconnor at gsoft.com.au> wrote:
> On Mon, 14 Jan 2008, Igor Mozolevsky wrote:
> > On 13/01/2008, Peter Jeremy <peterjeremy at optushome.com.au> wrote:
> > > IMHO, no.  Virtually all similar FreeBSD information is exported
> > > via sysctl and this sort of information fits neatly into the
> > > existing MIB tree as either dev.cpu.N.features or hw.cpu.features
> >
> > /dev/sndstat?
>
> A single handy counter example to the many many that are sysctls :)
>
> > If it's in /dev you can do neat tricks like ioctl-ing queries (like
> > ioctl(/dev/cpuinfo, CINFOCTL_HAS_FEATURES, CINFO_SSE3|CINFO_SSSE3))
> > instead of having *every* app parse the result of a sysctl; most of
> > the time you'd only want to check for specific feature , it's much
> > easier to do an ioctl that returns a boolean.
>
> Except you can't do that from a shell script.
> (eg wrapper script to run optimised binaries)

cat /dev/cpuinfo and parse away!


Igor