Getting swap info without kvm access

[Dan Nelson]

In the last episode (Jul 02), gomalley at mthoodcards.com said:
> I've written an Afterstep applet that retrieves and displays
> different time and system information.  The Linux port uses a few
> functions like gmtime() and gethostname() and reads most of the info
> from /proc files.  The FreeBSD port used the function calls and gets
> most of the info from sysctl() calls, except for the swap space.  As
> written now, that info is retrieved with kvm_getswapinfo().  The
> problem is that that function requires access to /dev/mem which isn't
> available without sgid privileges.  The current work-around is to
> display 0 for swap space if the applet is running un-privileged.
> 
> I've searched and browsed the mailing lists, I've poured over the
> .h's, .c's, sysctl -a and man pages for weeks but I'm stumped.  Is
> there some way to get total and either free or used swap space
> without using /dev/mem?  If not, why is that one piece of info not
> available through a sysctl() call?

It is in 5.x.  The kvm_getswapinfo() function reads the vm.swap_info
sysctl when getting status on a live system.  You'll just have to
install the applet setgid kmem to get swap info on 4.x.
 
-- 
	Dan Nelson
	dnelson at allantgroup.com