Setup

            sudo su  	

           	wget http://safe-power.appspot.com/scripts/install.sh  	

        	chmod +x install.sh   

        	./install.sh 

        	


        	



            $  apt-get install scribbler
            $  gem install scribbler
          

            sudo su  	

           	cd /bin  	

        	nano safe-power.py   

        	

        	

        	



            $  apt-get install scribbler
            $  gem install scribbler
          

#!/usr/bin/env python  
#script to shutdown the raspberry by safe-power raspberry UPS
#save this script as root under /bin/safe-power.py  
#add this script AS LAST LINE of root's crontab in the following way
#  @reboot /bin/safe-power.py & 
# important!! dont forget the "&"  in the end!!
#the script will be started in the background at reboot 
#and safe power will be operational
import RPi.GPIO as GPIO  
GPIO.setmode(GPIO.BCM)  
import os   
import time
# GPIO 11 = pin23 set up as input. It is pulled up to stop false signals  
GPIO.setup(11, GPIO.IN, pull_up_down=GPIO.PUD_UP)
# now the program will do nothing until the shutdown signal on pin 23   
# gets LOW.     
#During this waiting time, your raspberry is not 
#wasting resources by polling the pin
  
try:  
    GPIO.wait_for_edge(11, GPIO.FALLING)
 
# warn all logged users of the shutdown event
    os.system("wall shutdown by UPS")
#now the system will shut down
    os.system("sudo poweroff")  
#except if this script will be cancelled by the user explicitely
except KeyboardInterrupt:  
    GPIO.cleanup()       # clean up GPIO on CTRL+C exit  
    GPIO.cleanup()           # clean up GPIO on normal exit 

Save the file by hitting CTRL+x and y.
change the permissions of your script with:

            sudo chmod +x /bin/safe-power.py 

edit the crontab by issuing the following command

            crontab -e 

paste the following line at the LAST LINE of the crontab

@reboot /bin/safe-power.py & 

save your root's crontab by hitting CTRL+x and y(or whatever your editor expects)
Your safe-power will be operational at next reboot

            ps -ef | grep safe   

            
          



            
          

root       296     1  0 Jun04 ?        00:00:00 python /bin/safe-power.py

            sudo  /bin/safe-power.py 

            sudo crontab -e   

            
          



            $  apt-get install scribbler
            $  gem install scribbler
          

@reboot /bin/safe-power.py &

If it is not there, insert it manually or use the install script