PERFORCE change 122077 for review

[Roman Divacky]

On Thu, Jun 21, 2007 at 10:01:06AM +0000, Roman Divacky wrote:
> http://perforce.freebsd.org/chv.cgi?CH=122077
> 
> Change 122077 by rdivacky at rdivacky_witten on 2007/06/21 10:00:59
> 
> 	Introduce kern_absolute_path which checks whether a given path is absolute or
> 	not by checking first char for being '/'.
> 	
> 	Use this function to implement BADF semantic of *at syscalls.

there is a race condition pointed out by kib@, the path string can change
between calling the kern_absolute_path and the actual use in namei.

I'll work on it