script to poweroff when running on UPS

[wrapster]

Hi all,

The place where i stay experiences lot of power cuts and my solaris box is almost always on.
It so happens that many times i will not be around to switch it off as soon as there is a power cut..(i also have UPS which provides alternative supply for 15min)
So i wanted to write a script that can actually sense a power cut ,or at least sense that the power is being supplied from UPS and then automatically switch off....

I would like to try and write a script myself ,but dont know where i should start looking for the changes in the parameters when there is a power cut?
So could you please let me know where i can get these informations from and how i can use it in a script to initiate a shutdown?
Just a brief overview is sufficient ,as i would like to try writing a script myself...
If i cannot i will revert back!!!!

Thanks

[meton_magis]

i have no idea for solaris, but in redhat based systems, in /etc/inittab there is a line for what to do if the UPS goes out. may want to check there.