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SubjectRe: Patch for 2.2.10 (Quelle surprise!)

Jes Sorensen writes:
>> "Alex" == Alex Buell <alex.buell@tahallah.demon.co.uk> writes:
>>> On Mon, 5 Jul 1999, Stephen C. Tweedie wrote:

>>>> Basically it just returns a structure filled out with
>>>> processor information a la 'cat /proc/cpuinfo', except that
>>>> this is done via a syscall - no more horrid /proc parsing.
>>>
>>> That is exactly the sort of thing that sysctl() was designed for.

I think sysconf() is what you are looking for.
Pick a range of numbers to reserve for kernel use.
For example, 0x0a000000 to 0x0affffff would do.

Usage: smp_num_cpus = sysconf(_SC_NPROCESSORS_CONF);

Try to get this correct too:

RETURN VALUE
The value returned is the value of the system resource, 1
if a queried option is available, 0 if it is not, or -1 on
error. The variable errno is not set.

You must not ever return 0 for an error condition.
Errors are -1.

>> OK, I've heard the same thing from a number of people. Looks
>> like I'll be spending some time re-implementing the work I've
>> done as a sysctl().
>>
>> Thanks for all the input, guys.
>
> You still haven't explained why a syscall/sysctl is needed for this
> when all the information can be obtained by parsing /proc/cpuinfo

Obviously you haven't tried this in a cross-platform manner.
(or you wrote the libc 6 sysconf() hack and think your code works)

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