UNIX for Dummies Questions & Answers

Hi!
I want to test something to learn Shell scripting better.

1)
How can I make a BackUp from all users and groups homedirectory?

I want to save that backup in an archiv.
Can I choose how to name the backUp archiv?

2)
Ok I want to make a file like csv, in this file are listed Users.
How can I read the file and then from the given info create as many users as they are inside the file?
I think I have to use a for loop...?

I just started yesterday with this, only now the loops and variables etc.

Hi there!

1. You can use tar to create backup:

Code:

tar cvf home-backup.tar /home
## The below works on Linux or systems using GNU tar
tar cvzf home-backup.tar.gz /home

2. Try to understand this code on your own; you will be good to go

Code:

 sed -e 's/\,/\n/g' my_csv_file | while read name; do /usr/sbin/useradd "$name"; done;

Ohh forgot to tell you this: Happy Learning

Code:

 -e 's/\,/\n/g'

What does the -e mean?

And if I create a user like this

Code:

useradd Name -p Passwort

I cant login with this user??

-e switch is used to define one executable block of sed. You can simply ignore this in this case; however, it's very useful when you want to process a text multiple times with different regular expression. For an example:

Code:

sed -e 's/ /\n/g' -e '/^$/d' file

This replaces spaces with new line as well as deletes any empty line in file. You could do this with help of pipe and running sed (without -e switch) two times (takes more time than the above one):

Code:

sed 's/ /\n/g' file | sed '/^$/d'

You can use the -p switch to enter encrypted password for the new user. So, if you are simply entering the password with the -p switch, it's not going to work.