Upload
rohit-kumar
View
821
Download
0
Embed Size (px)
DESCRIPTION
Citation preview
Linux History & Features
Roadmap
What is Unix? What is Linux? Which Linux Distribution is better? Linux : Advantages & Disadvantages Basic Commands Vi and Emacs Available Software Web Server
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
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
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
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, …
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.) …
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.
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.
Basic Commands
ls $ ls -l $ ls -a $ ls -la $ ls -l --sort=time $ ls -l --sort=size -r
cd $ cd /usr/bin
pwd $ pwd
~ $ cd ~
~user $ cd ~VeerBahadur
which $ which ls
whereis $ whereis ls
locate $ locate stdio.h $ locate iostream
rpm $ rpm -q bash $ rpm -qa $ rpm -qa | sort | less
find $ find / | grep stdio.h $ find /usr/include | grep stdio.h
Vi
2 modes Input mode
ESC to back to cmd mode Command mode
Cursor movement h (left), j (down), k (up), l (right) ^f (page down) ^b (page up) ^ (first char.) $ (last char.) G (bottom page) :1 (goto first line)
Swtch to input mode a (append) i (insert) o (insert line after O (insert line before)
Delete dd (delete a line) d10d (delete 10 lines) d$ (delete till end of line) dG (delete till end of file) x (current char.)
Paste p (paste after) P (paste before)
Undo u
Search /
Save/Quit :w (write) :q (quit) :wq (write and quit) :q! (give up changes)
Emacs
$ emacs Cursor movement
^f (forward one char.) ^b (backward one char.) ^a (begin of line) ^e (end of line) ^n (next line) ^p (prev. line) ^v (page up) alt-v (page down)
Deletion ^d (delete one char) alt-d (delete one word) ^k (delete line)
Paste ^y (yank)
Undo ^/
Load file ^x^f
Cancel ^g
Save/Quit ^x^c (quit wiout saving) ^x^s (save) ^x^w (write to a new file)
Available Software
Compilers: G77 (FORTRAN 77) Gcc ( C ) g++ (C++)
Text editors Emacs
Typesetting Troff, TeX
Graphing Gnuplot
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.
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.
User Management
Common files to look at /etc/passwd /etc/group /etc/shadow /etc/samba
Web server on Linux
Apache server is mostly available on LinuxRpm –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
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 !!
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?
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
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
Presented By : Beer Bahadur Singh
Designation : Asst. S/W Engineer(Trainee)
Id No : VGT 153 T