How to get the system is doing reboot or shutdown？

[gkm]

I wrote a service script in /etc/init.d
How can I get the system is doing reboot or shutdown in the script
I need to do some different work when reboot and shutdown

[TrevorH]

For CentOS 7 you probably should be using unit files not initscripts. And I doubt if there is a way since they are effectively the same thing - restart is shutdown then restart, shutdown is just shutdown.