[SOLVED] Begginer's bash script question

MrNatewood · 02-15-2011, 04:38 AM

Hello,

I am administrating a lab in a university and every semester we need to delete all the home folders of the accounts for the next semester.

I would like to make a bash script that does this automatically and having trouble with it.

Note that I am writing my very first bash script.

What I need to do is make a script to delete the following:
Delete everything in /home/$exp$num/$dir
when "exp" could be either "rt", "ic" or "sp".
"num" could run from 1(single digit) to 45 and dir is "profile" and "work".

This is what I tried to write:

Code:

#!/bin/sh

cd /home

for exp in "rt ic sp"
do
	for num in "1 2 3 4 5 6 7 8 9"
	do
		for dir in "profile work"
		do
			rm -r $exp$num*/$dir/*
done
done
done
exit 0

What seems to be the problem is the reading of "$exp$num" as a joint expression.

Can anyone tell me what exactly am I doing wrong?

corp769 · 02-15-2011, 04:47 AM

Code:

#!/bin/bash
rm -rf /home/rt*
rm -rf /home/ic*
rm -rf /home/sp*

Would that be a possible solution? Dirty, but easy.

MrNatewood · 02-15-2011, 04:53 AM

Thank for suggestion but the problem with that is that there is a directory that needs to saved inside the tree.

For example in /home/rt1
There are three directories
/home/rt1/profile
/home/rt1/work
/home/rt1/RT-DSP

The last of which needs to be saved. I need to only delete "work" and "profile".

Moreover, there are some other users that start with "ic" or one of the others and does not continue with a number. you can imagine a user named "iceweasel" being deleted.

Dark_Helmet · 02-15-2011, 05:07 AM

1. I don't follow you when you say "joint expression." What exactly do you mean by that?

2. I also don't understand why your rm command uses two asterisks. In your original post, you say you want to "Delete everything in /home/$exp$num/$dir" but then you use "rm -r $exp$num*/$dir/*" to do the deletion. If that were to work as I think you expect, when num=1, your rm command would delete numbered directories 1, 10, 100, 1000, 11, 12, 13, 1a, 1b, 1c, 1A, 1B, 1C, etc. And of course, similar behavior when num=2 and so on. If you want num to go from 1 to 45, might I suggest:

Code:

for num in $( seq 1 45 )

Now, I don't know if this will fix your problem (see question #1), but it's good practice to always wrap your variables with curly braces. If you form the habit, you'll never have to worry about special cases when you must use them. In my opinion, they also make the script easier to read. For instance:

Code:

#!/bin/sh

cd /home

for exp in "rt ic sp"
do
	for num in $( seq 1 45 )
	do
		for dir in "profile work"
		do
			rm -r ${exp}${num}/${dir}/*
                done
        done
done
exit 0

MrNatewood · 02-15-2011, 05:20 AM

Thanks for all the tips.

The problem was with the quotes in the variable condition(should be rt sp ic and not "rt sp ic").
It is now working well without the quotes.