| SM1:
Open-source Operating Systems |
ASIX/DAW/DAM-1
|
Task A2: Basic command-line utilities. The
Linux directory tree |
2-10-2023 |
Task A2: Basic command-line utilities. The Linux directory
tree
GENERAL CONDITIONS
1- Deadline: 22-10-2023.
2- Send your report attached to an e-mail with the
following specifications:
a) E-mail
address: cf(at)collados.org or jordi.binefa(at)fje.edu
depending on who is your teacher
b)
File Name:
b.1) ASIX1: asix1_surname_name_sm1act02.pdf and asix1_surname_name_sm1act02.odt
b.2) DAW1: daw1_surname_name_sm1act02.pdf and daw1_surname_name_sm1act02.odt
c) Subject:
c.1) ASIX1:
asix1_surname_name_sm1act02
c.2) DAW1:
daw1_surname_name_sm1act02
3- Make this report individually.
4- Left, right, top and bottom margins: 2cm.
5- Character format: a) Font: Arial, b) Size: 10, c)
Questions typeface: Bold, d) Answers typeface: Regular
DOCUMENTATION
1- The Linux directory tree structure. Important files and
their paths
Read the following link:
https://www.howtogeek.com/117435/htg-explains-the-linux-directory-structure-explained/
At the moment, you should pay special attention to the following
directories (or folders):
a) /
|
d) /home
|
g) /usr/bin
|
b) /bin
|
e) /root
|
h) /usr/sbin
|
c) /etc
|
f) /sbin
|
|
But in the future we will pay special attention to /boot,
/dev, proc, mnt and /var directories as
well.
2- ls
a) The
ls command-line utility
lists directory (folder) contents.
b) Examples:
1) ls
--> Lists the contents of the present directory.
2) ls
-ls --> Lists the contents of the present directory
and extra information about each file or directory (owner,
size, permissions,.....)
3) If you want to list the contents of any folder, you
have to write its path. For instance:
ls -ls / --> Lists the contents (and extra
informatiosn) of the / directory.
ls -ls /home --> Lists the
contents (and extra information) of the /home directory.
ls -ls /var/lib --> Lists the contents
(and extra informatiosn) of the /var/lib directory.
4) If you want to list information about an specific
folder but not about its contents you have to add the
option -d. For instance:
ls -ls -d
/home or also ls -lsd /home
5) If you want to show
hidden files or directories inside a directory, you have to
add the option -a. For instance:
ls -a /etc/skel --> Lists hidden
files inside /etc/skel
3-
cat
a) The cat command-line
displays the contents of a text file. For instance: cat /etc/resolv.conf
displays the contents of resolv.conf.
b) If a text is
longer than one screen, you can use the special character |
and the command more
that displays as much as can fit on the current screen and waits
for user input (enter for a new line or space bar for a new
screen) to advance. For instance: cat
/var/log/messages | more.
4- cd
a) Description:
The cd command-line
utility changes the current working directory to a new working
directory.
b) Synopsis: cd directory_name
where directory_name is the name of the new working directory.
c) Examples: cd /home, cd /var/log, .......
d) Special cases and
special characters:
cd .
--> Changes to the
current working directory. The "."
character means "the current working directory".
cd .. --> Changes to the parent directory of the current
working directory. The ".."
character means "the parent directory of the current working
directory".
cd ~ --> Changes to
the user's personal directory which is "/home/username". The "~" indicates the user's
personal directory.
cd -
--> Changes to the previous directory. The "-" indicates the previous
directory
5-
Special character * (asterisk)
a) The asterisk * character is a special
character that causes the shell to generate filenames. It matches
any number of characters in a filename. For instance, if you want
a list of files in a folder that begin with the string "prov" then you can run the
command: ls -ls
prov*.
b) Examples:
dacomo@inf1-dacomo:~>ls
(with no *)
amemo mem memalx
memo memo.0612 memoa
memoalx.0620 memoalx.keep
memorandum
memosally sallymemo
typescript user.memo
It shows all files in the working directory
dacomo@inf1-dacomo:~>ls
memo*
memo memo.0612
memoa memoalx.0620
memoalx.keep memorandum
memosally
It shows all files in the working directory whose name
begin with the string memo
dacomo@inf1-dacomo:~>ls
*mo
amemo memo sallymemo
user.memo
It shows all files in the working directory whose name
end with the string mo
dacomo@inf1-dacomo:~>ls
*alx*
memalx memoalx.0620 memoalx.keep
It shows all files in the working directory whose name
contain the string alx
dacomo@inf1-dacomo:~>ls
*.*
memo.0612
memoalx.0620 memoalx.keep
user.memo
It shows all files in the working directory
whose name contains one or more extensions
dacomo@inf1-dacomo:~>ls
!(*.*)
amemo
mem memalx memo memoa memorandum
memosally sallymemo typescript
It shows all files in the working directory
whose name does not contain any extension. The special
character ! means: the opposite of, reverse,
negate, logical operator NOT.
6- Special character ~)
a) The ~ character means "personal folder". For instance,
if your user is called dacomo then ~ = /home/dacomo
b) You can combine ~ with a lot of commands on
Linux. For instance, if
your user is called dacomo then:
cd ~ => cd
/home/dacomo
ls ~ => ls
/home/dacomo
7- cp
a) Description: The cp command-line utility copies
one or more files and directories to a destination directory.
b) Synopsis: cp source_file destination_file
where source_file is the
name of the file that cp will copy, and destination_file is the name
that cp assigns to the new copy of the file. By
default, the destination_file
will be equal to the source_file.
c) Examples:
cp /var/log/messages
/media/usb/ --> A
file called messages in
the directory /var/log will
be copied in the directory /media/usb.
The name of the new file will be messages.
cp
/var/log/messages /media/usb/messages.20131110 -->
/var/log/messages
will be copied in the directory /media/usb. The name of the new file will messages.20131110.
cp
/var/log/* /media/usb --> All the files in
the directory /var/log
will be copied in the folder /media/usb.
d) Note: you can use .,..,- and ~.
8- mv
a) Description: The mv command-line utility moves
one o more source files and directories to a destination
directory. The original files will be removed. Refers to cp for Synopsis and examples.
b) Note 1 : you can use
the following special characters: . .. - ~
c) Note 2: You can
use mv to rename a
file --> mv
old_name new_name
d) Note 3: You can
use mv to move a
directory --> mv
existing_directory new_directory
9- mkdir
a) Description: The
mkdir command-line utility
creates a new directory..
b) Synopsis: mkdir directory_name
where directory_name is the name of the new created directory.
c) Examples:
mkdir
test00 -> Creates a new directory called test00 as a child of the
current working directory.
mkdir
/home/etpclot/test01 -> Creates a new directory
called test00 as a child
of the /home/etpclot
directory.
d) Note: you can use .,..,- and ~.
10- rm
a) Description: The rm command-line utility remove
files or directories. By default it does not remove directories.
b) Synopsis 1: rm file_name where file_name
is the name of the file that will be removed. Example: rm
/home/usuari/INDEX.gz.
c) Synopsis 2: rm -r directory_name
where directory_name is the name of the directory that
will be removed. Example: rm -r
/home/etpclot/test00.
d) Note 1 : you can use . .. - ~
e) Note 2: rm !(filename) removes all
files with the only exception of filename. For instance, if
you run rm !(ex01.c), every file in the directory
is removed with the
only exception of ex01.c. The special character ! means: the
opposite of, reverse, negate, logical operator NOT.
11- gzip
a)Description: The gzip command-line utility compresses or expand
files. A file compressed with gzip
is marked by a .gz
filename extension.
b) Synopsis 1: gzip
file_name where file_name is the name of the
file that will be compressed. Example:
gzip /home/etpclot/INDEX. After runing the
command, the original file will be replaced with a new file
called INDEX.gz.
c) Synopsis 2: gzip -d
file_name.gz where file_name is the name of the
file that will be expanded. Example: gzip -d /home/etpclot/INDEX.gz.After runing the command, the original file will be
replaced with a new file called INDEX.
d) Synopsis 3: gzip
-l file_name.gz where file_name is
the name of a compressed file. Option -l lists
the following fields: size of the
compressed file, size of the
uncompressed file, compress ratio and uncompressed
name.
12- tar
a) Description: The tar command-line
utility packs and
creates a new single file, which will be marked by a .tar filename extension,
from multiple files or directories hierarchies. The tar
comand-line utility can extract (unpack) files from a .tar file as well..
b) Synopsis 1: tar
cf filename.tar list_of_files
where filename.tar is the name of the .tar file that will
be created and list_of_files is a list of files (* can
be used).
c) Synopsis 2: tar
xf filename.tar where filename.tar
is the name of the packed file that will be unpacked.
d) Synopsis 3: tar
cf filename.tar directory_name where filename.tar is the name of
the .tar file that will be created and where directory_name is a directory that
will be packed.
e) Synopsis 4: tar tf filename.tar shows the
contents of filename.tar.
f) Examples:
tar cf test.tar
test00.c test01.c test02.c asm.hex
TODO.txt --> Creating a a new file test.tar
that packs test00.c
test01.c test02.c asm.hex and
TODO.txt
tar cf test_c.tar
test*.c --> Creating a new file test.tar that packs .c
files
tar xf test.tar
--> Unpacking test.tar
tar cf home.tar /home
--> Creating a new file home.tar that packs the
content of /home
tar tf test.tar
-->
Showing the contents of test.tar
13-
wget
a) Description: It
is a command-line utility for non-interactive download of
files from the Web.
b) Synopsis: wget URL where
URL is the web address of any resource on internet or
the LAN.
c) Exemple:
wget
http://www.collados.org/asix1/m01/asix1_m01_eng.pdf
--> Get and download asix1_m01_eng.pdf
14- which
a) Description: which shows where the
binary file (also called executable) of any command/program that
has been installed on your file system
b) Synopis: which
command_name, where command_name
is the name of a command-line utiliy (for instance mkdir)
c) Example: which mkdir
15- locate and update
a) Description: The
locate command-line utility finds (or locates)
files by name.
b) Installation:
* Run as a root user: aptitude
install mlocate.
* Afterwards, as a root
user, run:
updatedb (!!!!Very important --> If you do not
run this command, mlocate does not work
properly)
c)
Example:
* locate -b '\resolv.conf'
--> Shows directories where a file called resolv.conf
is stored.
*
locate -b '*.conf' --> Shows
directories where any file with the
extension conf are
stored
* locate -b
'resolv.*' --> Shows
directories
where files
with the basename resolv and extensions are
stored.
* locate -r /environment$ ->
Show directories where a file called environment
(with no extension) is stored
PRACTICAL EXERCISE
VERY IMPORTANT: You
can not answer any question as a root user. You can only
answer the questions of this exercise as a standard
user!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
1- Answer
the following questions:
a) Where is the personal folder of
your standard user in the linux directory
tree?:
b) Where is
the personal
folder of root
user in the linux
directory tree?:
c) How is
called the main
directory of the
linux directory
tree?:
d)
Which are the
folders where
you can find
the system
administrator
(or root)
binaries
(applications,
command,...)?:
e)
Which are the
folders where
you can find
binaries used
by standard
users?:
2- Change to the /usr/share/grub
directory using a single command. List the directory
contents showing
additional relevant information about the them (owner,
permissions, size, creation date, etc...).
3- Go back to your personal directory using a single
command. List
your hidden and unhidden files and folders, showing additional
relevant information about the them (owner, permissions, size,
creation date, etc...).
4- Create 3 new directories in your personal folder: task,
temp and help.
Show the contents of your personal folder.
5- Change to /usr/share/info directory. Copy gnupg.info.gz
and find.info.gz to ~/temp. List the ~/temp
directory contents.
6- Move ~/temp/find.info.gz
to ~/task. Change to ~/task. Check ~/task/find.info.gz
file size. Expand the file. Check the
new file size.
7- Copy ~/temp/gnupg.info.gz
to ~/help.
Change the name of ~/help/gnupg.info.gz
to ~/help/gnupginf.gz. List the ~/help
directory contents.
8- Remove gnupg.info.gz from ~/temp.
Copy ~/help to ~/temp. List the ~/temp
directory contents.
9- Remove the directories ~/temp and
~/task.
10- Show a list (displaying
relevant information) of:
a) All files in /bin containing "dt".
b) All files
in /etc ending
with ".conf".
c) All files
in /usr/lib/NetworkManager
starting with "nm-".
d) A list of files in the /etc/ssh
directory with no extension.
e) A list of files in the
/boot/grub directory whose name contains
one or more extensions.
11- Copy /usr/share/info/nano.info.gz
in your personal folder with the help of
the special character ~. Change to your
personal folder with the help
of the special character ~.
Show the contents of your personal folder
(hidden and not hidden) with the help of ~.
12- Run a command to check only
the size of nano.info.gz.
Extract the contents of nano.info.gz.
Check the size of the
extracted file nano.info.
Check that nano.info.gz
does not exist any longer.
13-
Create a
new directory called ~/tmp. Copy all
files in the /usr/bin directory that begin with the
character "z" to ~/tmp.
List the
contents of ~/tmp.
14- Change to ~/tmp.
Pack all files inside the ~/tmp
directory in a new file called zpack.tar.
Afterwards, compress zpack.tar.
Finally, with the only exception of
zpak.tar, remove all files
in ~/tmp with the help of !.
15-
Create
a new
directory
called ~/tmpl.
Copy all
files in the /usr/bin
directory
that begin
with the
characters "xd"
to ~/tmpl.
Pack
and compress
the
directory
~/tmpl
in a file
called tmpl.tar.gz.
Afterwards,
remove ~/tmpl.
Run
a command to
check the size
only of the
directory ~/tmpl.tar.gz.
16-
Create a
folder called
~/average.
Change to ~/average.
Download http://www.collados.org/asix1/m01/tu1/average.tar.gz
with wget.
17-
Extract and
unpack average.tar.gz.
Remove average.tar.
List the
contents of ~/average.
Show the
contents of average.c
and README
using cat.
18-
Find:
a)
Directories
where the
binary file of
gzip, gcc
and geany
have been
stored. Please
note that