Making sudo give a lecture every time it is used.

sudo command needs to be used with caution and sometimes we might need make this caution obvious with a message .
There is an option in sudo using which we can inform the user about using sudo with a message every time sudo is used.

Open the file /etc/sudoers

sudo vi /etc/sudoers

Add the following line after the intial comments to make sudo to throw the lecture every time sudo is used by a user.

Defaults lecture=always

If giving lecture every time seems like an overkill, it can be made to lecture only once when a user uses the sudo for the first time. Defaults lecture=once

The message that is shown by default is

$ sudo -i We trust you have received the usual lecture from the local System Administrator. It usually boils down to these three things: #1) Respect the privacy of others. #2) Think before you type. #3) With great power comes great responsibility.

Instead of the above message, we can show our own customized message by putting the message into a file. for e.g. let us put the following message

Please be careful while using sudo, you could fry the system.

In a file called lecture ,under the folder /home/user .

To make sudo use this file for the lecture message add the following line after enabling the lecture as shown above.

Defaults lecture_file=/home/user/lecture

Save and quit the file. The next time we use the command sudo, we should see the above message being shown.