/tmp on Linux

I know /tmp as it named is a temporary dircory, Debian policy is to clean /tmp at boot. However, I'd like to configure my Ubuntu Server to stop deleting files from /tmp on boot due to custom configuration issue. How do I configure behavior of boot scripts to stop deleting files on boot?

Users should not store files in /tmp, use /home or other partition, if you would like to keep the files. The behavior of boot scripts is controlled via a special configuration file called /etc/default/rcS. Open this file and modify TMPTIME variable.

On boot the files in /tmp will be deleted if their modification time is more than TMPTIME days ago. A value of 0 means that files are removed regardless of age. If you don't want the system to clean /tmp then set TMPTIME to a negative value(-1) or to the word infinite.

Configuration /etc/default/rcS

Open /etc/default/rcS file, enter:$ sudo vi /etc/default/rcS
Set TMPTIME to 60 so that files in /tmp will deleted if their modification time is more than 60 days ago.TMPTIME=60
Close and save the file. This configuration is used by /etc/init.d/bootclean script on boot to clean /tmp and other directories under all Debian based Linux distros.