Linux – “reboot” or “shutdown -r now”: what restart command is safer

launchctl(8) is your friend. Just keep in mind that some of the services (sshd for example) are disabled in the configuration file so you will need to use the -w switch when loading them. Here is a sshd example:

$ sudo launchctl load -w /System/Library/LaunchDaemons/ssh.plist 

You can stop the service using the unload subcommand.

$ sudo launchctl unload  /System/Library/LaunchDaemons/ssh.plist 

To list the services, as you might have already guessed use the 'list' subcommand ;)

If your hardware is ACPI compliant, the archlinux wiki outlines a process which may work for you using a package called acpid. I've had success with this method on other distributions.

https://wiki.archlinux.org/index.php/Shutting_system_down_by_pressing_the_power_button