cvs commit: src/sys/sys sysctl.h

[John Baldwin]

On Monday 31 December 2007 04:12:05 pm John Baldwin wrote:
> jhb         2007-12-31 21:12:05 UTC
> 
>   FreeBSD src repository
> 
>   Modified files:
>     sys/sys              sysctl.h 
>   Log:
>   Add very basic support for the kernel to export a list of features.  Each
>   feature is represented by a node in the new 'kern.features' sysctl node.
>   A feature is present if the corresponding node is present and evaluates to
>   true.
>   
>   A FEATURE() wrapper macro is added which takes the sysctl node name and
>   a description of the feature as the sole arguments and creates a read-only
>   sysctl node with a value of 1.
>   
>   Discussed on:   arch

Note that this is only the kernel side.  I'm not sure what the userland 
interface will look like.  It may be that each feature gains a new sysconf(3) 
constant rather than adding a new 'feature_present(const char *)' function.  
Also, I went ahead and put this into sys/sysctl.h rather than a new header 
because it was only 2 lines of code.

-- 
John Baldwin