How to remove entries in the client list?

Can anyone advise on how to write this to a script? I am trying to set things up so these commands run on boot, but, for me at least, the ‘service gl_tertf stop’ command is running into errors when executed through a script. It seems to not understand what ‘service’ is.

Edit: Silly me, it’s easier to just add two lines of code to remove the backup files at the beginning of the start_service() function of /etc/init.d/gl_tertf.