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)
13. Available Software Compilers:  G77 (FORTRAN 77)  Gcc ( C )  g++ (C++) Text editors  Emacs Typesetting  Troff, TeX Graphing  Gnuplot
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 SinghDesignation : Asst. S/W Engineer(Trainee)Id No : VGT 153 T