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  From: Avery Pennarun <apenwarr@worldvisions.ca>
  To  : <craigm@milkyway.gsfc.nasa.gov>
        < apmd-list@worldvisions.ca>
  Date: Wed, 26 May 1999 17:11:51 -0400

Re: pre-suspend notifications?

On Tue, May 25, 1999 at 02:45:08PM -0400, Craig Markwardt wrote:

>  > I'm still kind of confused about how it works.  If I'm listening for APM
>  > events, does that mean that some other process cannot also be listening
>  > for events?  I want to make xscreensaver passively observe the apm
>  > goings-on without influencing them.
> 
> The kernel allows multiple user-level programs to monitor APM events,
> but xscreensaver may have to be root to do this.  I agree that it
> would be desirable for user programs to get at this information
> without being root.  The problem is that customers of /dev/apm also
> have the ability to trigger apm suspend and standby mode, which could
> be a security risk if everybody can do it.

As far as I can tell, at least in 2.2 kernels, access to /dev/apm_bios is
controlled only by file permissions.  Is there a security risk in

	chmod a+r /dev/apm_bios?

Have fun,

Avery