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History of Linux

In 1969, Four programmer Ken Thompson, Dennis Ritchie, Rudd Canady & Doug

McElroy made a

program in Bell labs which does not have any name in year 1969.

Brian Kernighan checked that program & found it is very good software for client &

networking

purpose. He gave the name Unix to this program on 1st J anuary 1970 (epoch time).

First Operating System.

That time that program was written in Assembly language.

In 1972, a programmer Dennis Ritchie started converting this program in C

language. (Also called

founder of C language).

1973- Unix in C language.

1980- Berkeley Software Development (a part of research program of Berkeley

University)

launches open BSD (a small program written in a single floppy).

Paul Allen & Bill Gates are the employee of Bell Labs.

In 1981, they both started Microsoft with 9 more candidates & they gave a

programme named

Xenix (1980) but it was flopped.

In 1981- Launched MS-DOS 1.0

In 1984- UNIX open source

In 1985- First Graphical Based OS- Win 2.0

In 1991, Linus Benedict Torvalds, B-tech I ind year Computer Science, 23 years old

student of

University of Helensiki (Finland) made Kernel (25th August 1991).

In 1994- RedHat Company (collection of Linux Sets) came into existence.

99 % servers of Linux till 2012.

LINUX PRINCIPLE

1. Everything is a file.

2. Small, single purpose programmers

3. Ability to Chain programmers

4. Avoid captive user interfaces.

5. Configuration data stored in text.

Linux Directory Structure

/ home Users home (all users folders)

/bin Commands (user executable & Scripts)

/usr/bin Commands (user executable & Scripts)

/ sbin root privileged command

/usr/local/bin commands which we make for our use.

/etc System Configuration files

/boot Linux Kernel & Bootable files

/ root root (Admin) Data

/mnt for mounting any external devices

/dev devices (hdd, CD-Rom, Pen Drive)

/ srv Server data

/ sys System Information

/ lib Library files stored

/proc virtual file system

/ tmp Temporary files

/var Variable file (database,logs)

/opt Add on Application software

Linux Basic Commands

Directory commands:

1. # mkdir - For creating directory.

2. # cd - change directory.

3. # cd .. - to come out from working directory.

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4. # rmdir - to remove directory

File Commands:

1. # touch - creates a blank file.

2. # cat > filename - creates a file and for saving this file (ctrl + D)

3. # cat - to see the content of the file.

4. # cat file1 >> file2 - to move file1 matter in file2

5. # cat -n filename - to see how many lines are written in that file.

Commands for deleting:1. # rm filename - deletes a file.

2. # rm -i - deletes file/folder in interactive mode (asking mode)

3. # rm -r - deletes directory.

4. # rm -f - deletes files/ folders forcefully.

Help Commands:

1. # whatis These all are the help commands. Prints all related tags

2. # man about that command.

3. # info

4. # --help

5. # which

6. # cd /usr/ share/doc

Rename & Move:

1. # mv (Rename)2. # mv (Move)

Listing Commands:

1. # ls - listing files/ folders

2. # ls -l (ll) - long listing of files/folders with whole information

3. # ls -a - lists all files/ folders (hidden also)

4. # ls ??? - all files/folders named with 3 characters

5. # ls m* - files & directories started with letter m.

Copy:

1. # cp - copies files from source to destination

2. # cp -i - copies files from source to destination in asking

mode

3. # cp -i * - copies current working directory all data to destination.

4. # cp -r - copies directory from source to

destination

Editors in linux:

1. nano

2. vi These editors are used in console mode.

3. vim

4. gvim

5. gedit These editors are used in graphical mode.

6. Emacs

VI editor/ VIM editor:

There are three modes in vi editors

1. ex mode (default mode, by pressing escape key, this mode is used for saving and

exit )2. Insert mode (by pressing insert or I key, this mode is used for editing)

3. Replace mode (this mode is used for replacing text written, by again pressing

insert or r key)

For saving document- come on esc mode and write :wq

For setting line numbers in document come on esc mode and write : se nu

For coming on any specific line press line no. and then G (ex- 102 then G) or :line

no (enter)

For going at the end of page press G

For going at the top of page press gg

For searching any text in the file /text

For undo u and for redo ctrl+r

Vim editor is not installed default when you install linux, you have to install vim

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editor. I t is the

enhanced version of vi editor.

# vim/vi filename

Press v to come to visual mode, here we can select the matter which we want to

copy , press yy

to copy (y stands for yank). Press p to paste that matter.

Press dd to delete a particular line where cursor is.

Nano Editor:

Nano is a command based editor, earlier used when advanced editors were not

came into being.When you open a a file with this editor, you will find all related help of this

command.

SOME BASIC COMMANDS

1. # poweroff -f

2. # halt -n -p - These commands are used to turn off computer.

3. # init 0

4. # init 6 - These commands are used to Restart computer.

5. # reboot

6. # startx - Switch from command to graphic.

7. # init 5 - Restarts system from command mode to graphic mode.

8. # history - To see history of recent commands.

9. # history -c - To clear the history of recent commands

10. # cat > /etc/ issue - To create logoff scripts.

11. # cat > /etc/motd - To create logon scripts.12. # cal yyyy or mm yyyy - To see the calendar of that month & year.

13. # bc - Starts basic calculator.

14. # whoiam or # w - To know by which user we logged on

15. # adduser - To create user

16. # passwd - To give password to user.

17. # userdel - To delete user.

18. # usermod -L - To lock a user account.

19. # usermod -U - To unlock a user account.

20. # passwd -d -To remove password for a user.

21. # cd ~ - Switch directly to users home directory with.

22. # head - To see the top ten lines of a file.

23. # head -n 16 - To see top 16 lines of a file.

24. # tail - To see the bottom ten lines of a file.

25. # tail -n 16 - To see bottom 16 lines of a file.

26. # evince - To open a pdf file (only on graphical terminal)

27. # sort - Sort fi le in a-z format.

28. # sort -d - Sort file in dictionary format.

29. # sort -r -Sort file in z-a format.

30. # sort -t : -k 3 n/ r/ u - Sort the file according to given delimiter

(n=numeric, r= decending, u=removes duplication)

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