Re: sysctl(3) and sysctl(8) discrepancies

In the last episode (Apr 19), Mathieu Prevot said:
Hello,

I have FreeBSD 6.1-RC #27: Wed Apr 19 02:08:00 CEST 2006 amd64 and I have 3
different outputs about hw.ncpu:

`sysctl hw.ncpu` gives me:

'hw.ncpu: 2'


and I have:

hw.ncpu = 6
hw.ncpu = 3


with:

#include <stdlib.h>
#include <sys/types.h>
#include <sys/sysctl.h>

main()
{
int ncpu[1];
size_t len;

len=sizeof(int);
sysctlnametomib("hw.ncpu",ncpu,&len);

You want sysctlbyname() here instead. sysctlnametomib() returns a
pointer to a mib array that you can pass to the sysctl() function
later. Saves having to parse the string every time if you are looking
up the same sysctl repeatedly.

sysctlbyname("hw.ncpu", &ncpu, &len, NULL, 0);

HW_NCPU is the mib number for hw.ncpu if you want to build the mib
array manually.

--
Dan Nelson
dnelson@xxxxxxxxxxxxxxx
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