Checking sysctl values from within the kernel.

John Baldwin jhb at
Fri Aug 5 15:54:30 GMT 2005

On Friday 05 August 2005 10:50 am, Dan Nelson wrote:
> In the last episode (Aug 05), Thordur I. Bjornsson said:
> > If I want to check a sysctl value from within the kernel (e.g. an
> > KLD), should I use the system calls described in sysctl(3) ?
> >
> > If not, what is the propper way to do so ?
> Since most sysctls are direct mappings onto integer variables in the
> kernel, just check the variable directly.

There's also a kernel_sysctl() function available in the kernel for in-kernel 
access to sysctls.  You might have to lookup the OID for a given name 
yourself though.  Actually, there's a kernel_sysctlbyname() as well.

John Baldwin <jhb at>  <><
"Power Users Use the Power to Serve"  =

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