adding support for hibernation to xfce4-sessions's exit dialog

[Jani Monoses]

Rodrigo Coacci wrote:
> I guess it should also check for system capability for doing those
> things. I read somewhere else that a simple "cat /proc/something" or 
> /sys/something should do the trick. I'm telling this because if
> hibernate is called in a system no "ready" for it, it may cause real
> data loss.... I don't know how xubuntu ppl work around this, maybe they
> already have some better HAL-based solution

Asking HAL, but also allowing the user to disable suspend/hibernate from
the settings dialog, as having /sys/power or similar as you mention is
no guarrantee that hibernation works, it only says that support for it
is in the currently running kernel. Ubuntu uses a list of supported
laptops which are known to work but still user input is needed.

Jani