What these commands do?

[nujinini]

hello guys,

i was trying to do some scripting practice a while ago and nothing seems to be happening in the terminal. kindly refer below. was i doing it right? or perhaps nothing was really suppose to happen?
what's it suppose to do anyway. in what way can this commands be useful to me? really appreciate anyone who can help enlighten :confused

got this sample commands from Advanced Bash-Scripting Guide:

Example 2-1. cleanup: A script to clean up the log files in /var/log


# Cleanup
# Run as root, of course.

cd /var/log
cat /dev/null > messages
cat /dev/null > wtmp
echo "Logs cleaned up."

[darkrose0510]

This looks like homework, we don't do your homework for you here.

[GNU-Fan]

what's it suppose to do anyway.
in what way can this commands be useful to me?

You should never run scripts whose function is unknown to you as root.
The "man" command can give you an idea about what each command does, e.g. "man cat".

[nujinini]

You should never run scripts whose function is unknown to you as root.
The "man" command can give you an idea about what each command does, e.g. "man cat".

thanks a lot for this advise. very helpful for a newbie like me who wants to learn as much as i can learn...