Table of Contents

Chapter 3 Answers to Exercises in Section 3.6

Chapter 3 Answers to Exercises in Section 3.6

3.6.1. Partitions

Look in /etc/fstab or use df to see if /home is mounted on separate partition.
1. to see all partitions on the computer
```
fdisk -l
```
2. to see all mounted partitions
```
df
```
3. ```
fdisk -l | grep ^/ | wc -l
```
Add up the used space on partitions found from
```
df -h
```
First eliminate all /media directories with umount and then:
- ```
du -sh /
```

3.6.2. Paths

```
echo $PATH
```
This gives no ls command.
1. /home/username
2. ```
cd ../myusername
```
```
cd /var/tmp
```
```
cd /usr/share
cd doc
pwd
    
```

3.6.3. Tour of the system

1. cd /proc

2. less cpuinfo

3. less meminfo

4. less swaps

5. less modules

6. cat uptime

7. less filesystems

man proc
- Refer to the man page of proc for more info about these files

11. cd /etc

12. remove question

13. remove question

14.

less issue
less motd

15. Note: for just the normal users, check for bash with the second command

      wc -l /etc/passwd
      grep bash /etc/passwd |wc -l

16. wc -l /etc/group

17. /etc/timezone

18. find /usr -iname “*howto*”

19. cd /usr/share/doc

20.

cd /usr/share/doc/coreutils
      less README

or

info coreutils

21. From man bash: bash –version

3.6.4. Manipulating files

```
      cd ~
      mkdir newdir
    
```

No

mv newdir 
/home (error: Permission denied)

1. ```
cd /usr/share/pixmaps
cp *.xpm ~/newdir
      
```
2. With this command several programs are listed indicating that XPM is X PixMap
```
 apropos xpm 
```
```
ls -r
```
```
mkdir ~/newdir2
cp -r /etc/* ~/newdir2
    
```
- Note that you will probably be denied permission to some of /etc

cd ~/newdir2
mkdir Upper lower
find . -name "[A-Z]*" -exec mv {} Upper \;
find . -name "[a-z]*" -exec mv {} lower \;

find . -name "[!a-zA-Z]*" -exec rm {}  \;

```
rm -rf ~/newdir2 
```
Nothing found. Tried with xfs, server and font. No separate font server?
```
cd /etc/init.d 
grep font * |grep server 
    
```
sendmail not found. Most systems now use exim or postfix.
```
which sendmail 
locate sendmail
    
```

ln -s /var/tmp ~/mytmp
ls ~/mytmp (will see the contents of /var/tmp

```
cd ~
ln -s mytmp mynewtmp
rm mytmp
ls
  
```
- mynewtmp is now red on black indicating a broken link

3.6.5. File permissions (Warning: Do not do these as root or with sudo)

Only on the directory that you own-your home directory
```
 umask  
```
You cannot do this as normal user
```
 chmod o-r ~/.bashrc 
```
A long list of files scrolled by. Many were not in /root.
```
 ln -s /root ~/myroot
```
- Yes, I can read files there, but cannot create or modify files.

Home

Copyright (c) by the authors.
This section of the wiki is licensed under the terms of the GNU Free Documentation License.
See the LBook-licensing page for details.

Linux® is a registered trademark of Linus Torvalds.

LinuxBasics.org

The community that helps people to run Linux