This document provides an overview of Linux history and features. It discusses that Unix was developed in 1969 at Bell Labs and led to various variants. Linux was developed in 1991 by Linus Torvalds as an open source clone of Unix. It discusses some popular Linux distributions like Red Hat, Ubuntu, Debian etc. It then covers basic Linux commands, text editors like Vi and Emacs, available software packages, user management and how to setup a basic web server. It encourages computer engineers to learn Linux as most professional applications and tools are available on Linux platforms.
2. Roadmap
What is Unix?
What is Linux?
Which Linux Distribution is better?
Linux : Advantages & Disadvantages
Basic Commands
Vi and Emacs
Available Software
Web Server
3. What is Unix?
A multi-task and multi-user Operating System
Developed in 1969 at AT&T’s Bell Labs by
Ken Thompson (Unix)
Dennis Ritchie (C)
Douglas Mcllroy
Some other variants: System V, Solaris, SCO
Unix, SunOS, 4.4BSD, FreeBSD, NetBSD,
OpenBSD, BSDI
4. Before Linux: UNIX
Many difficulties in Multics development
1969
AT&T pulled out of Multics
Ken Thompson
A simplified version of Multics UNIX
Dennis Ritchie
Rewrite the UNIX in C
AT&T cannot sell the UNIX
UNIX is the first free Operating System
5. What is Linux?
A clone of Unix
Developed in 25 August 1991 by Linus Torvalds, a
Finish graduate student
Inspired by and replacement of Minix
Linus' Minix became Linux
Consist of
Linux Kernel
GNU (GNU is Not Unix) Software
Software Package management
Others
6. What is Linux?
Originally developed for
32-bit x86-based PC
Ported to other
architectures, eg.
Alpha, VAX, PowerPC,
IBM S/390, MIPS, IA-64
PS2, TiVo, cellphones,
watches, Nokia N810,
NDS, routers, NAS, GPS,
…
7. Which Linux Distribution is better?
> 300 Linux Distributions
Slackware (one of the oldest, simple and stable distro.)
Redhat
RHEL (commercially support)
Fedora (free)
CentOS (free RHEL, based in England)
SuSe ( based in German)
Gentoo (Source code based)
Debian (one of the few called GNU/Linux)
Ubuntu (based in South Africa)
Knoppix (first LiveCD distro.)
…
8. Advantages of Linux
Linux is free:
Price is zero.
Unlimited copies permitted.
Read and change source code.
Manuals are on-line.
Common in scientific circles.
Text interface is good for batch processing
and management.
9. Disadvantages of Linux
Text interface is not as user-friendly as
Windows.
But, has StarOffice software which is looks much
like Windows.
Less commercial software available.
But, more scientific software available.
More difficult to set up.
But, once set up, easy to manage.
10. Basic Commands
ls which
$ ls -l $ which ls
$ ls -a whereis
$ ls -la $ whereis ls
$ ls -l --sort=time locate
$ ls -l --sort=size -r $ locate stdio.h
cd $ locate iostream
$ cd /usr/bin rpm
pwd $ rpm -q bash
$ pwd $ rpm -qa
~ $ rpm -qa | sort | less
$ cd ~ find
~user $ find / | grep stdio.h
$ cd ~VeerBahadur $ find /usr/include | grep stdio.h
11. Vi
2 modes Delete
Input mode
dd (delete a line)
d10d (delete 10 lines)
ESC to back to cmd mode d$ (delete till end of line)
Command mode dG (delete till end of file)
Cursor movement
x (current char.)
h (left), j (down), k (up), l (right)
Paste
^f (page down)
p (paste after)
^b (page up)
P (paste before)
^ (first char.) Undo
$ (last char.) u
G (bottom page) Search
:1 (goto first line) /
Swtch to input mode Save/Quit
a (append) :w (write)
i (insert) :q (quit)
o (insert line after :wq (write and quit)
O (insert line before) :q! (give up changes)
12. Emacs
$ emacs Paste
Cursor movement ^y (yank)
^f (forward one char.) Undo
^b (backward one char.) ^/
^a (begin of line) Load file
^e (end of line) ^x^f
^n (next line) Cancel
^p (prev. line) ^g
^v (page up) Save/Quit
alt-v (page down) ^x^c (quit wiout saving)
Deletion ^x^s (save)
^d (delete one char) ^x^w (write to a new file)
alt-d (delete one word)
^k (delete line)
14. Available Software
StarOffice provides a Windows-like
environment:
Word processor
Spreadsheet
Overhead slide designer
Can load and save existing files created on a
Windows computer.
15. User Management
Simple way to add user is adduser command
Passwd will allow to change the passwd
Ofcourse there are host of GUI tools for all
these user management
Group all common user to single group
Be carefull while editing /etc/passwd
/etc/shadow passwd file may also exist.
16. User Management
Common files to look at
/etc/passwd
/etc/group
/etc/shadow
/etc/samba
17. Web server on Linux
Apache server is mostly available on Linux
Rpm –q –all | grep apache to check
This can be started via init services
/etc/rc.d/init.d/httpd start
Configuration files are at /etc/httpd/conf/
Normally log files at /var/log/httpd
18. Lost Root Passwd
If you have Lilo installed, type
LILI: linux init 1
Change the root passwd, reboot aga
If you have installed grub
Type ‘e’ to go to edit mode, add init 1
argument at the end
Boot with knoppix or single floppy linux
Mount the disk and change root passwd
Reboot !!
19. GNU/Linux & You (Computer Engineer)
Ok! ! !
Windows is more popular
90% of Desktop computers run Windows
But!
The 90% contains children, officers, …
How many CEs do use the Windows?
How many professional applications
(supercomputing) do use the Linux?
20. GNU/Linux & CEs
Linux is NOT for dummies
Linux is for CEs
Linux does NOT hide anything
In details boot message
Kernel messages
No registry All config files are text files
Using Linux needs computer knowledge
You have the knowledge
21. GNU/Linux & You
If you target PhD in Computer Science
You must learn Linux
Most tools, simulators, protocols, … are
implemented & tested in Linux
If you target Engineering in Iran
Linux Administrator
Linux Application developer
Embedded Linux Developer
22. Presented By : Beer Bahadur Singh
Designation : Asst. S/W Engineer(Trainee)
Id No : VGT 153 T