Linux Basics

WeeSan Lee <weesan@cs.ucr.edu>

http://www.cs.ucr.edu/~weesan/
cs183/
Roadmap

 What is Unix?
 What is Linux?
 Which Linux Distribution is better?
 Fish vs. Fishing
 Basic Commands
 Vi and Emacs
 Q&A
 References
http://www.cs.ucr.edu/~weesan/
cs183/
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 (Pipes - Do one thing, do it well)
 Some other variants: System V, Solaris, SCO
Unix, SunOS, 4.4BSD, FreeBSD, NetBSD,
OpenBSD, BSDI

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cs183/
What is Linux?
 A clone of Unix
 Developed in 1991 by Linus Torvalds, a Finnish
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
http://www.cs.ucr.edu/~weesan/
cs183/ http://www.linuxdevices.com/files/misc/ibm-watchpad.jpg
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,
…

http://www.cs.ucr.edu/~weesan/ * See references at the end

cs183/ for the corresponding websites.
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.)
 …
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cs183/
Which Linux Distribution is
better? Ubuntu
Debian
Knoppix

Slackware Gentoo

CentOS

Redhat

Source: http://www.cs.ucr.edu/~weesan/
cs183/
http://futurist.se/gldt/
Which Linux Distribution is
better?
 Ask yourself these questions (from LAH)
 Is it going to be around in 5 yrs?
 Is it giong to stay on top of the latest security
patches?
 Is it going to release updated software promptly?
 If I have problems, will the vendor talk to me?
 Personally, I use Slackware
 But, we will use CentOS (possibly along with
Slackware :)
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cs183/
Fish vs. Fishing
 Manpage  4 Device drivers and
 $ man ls network protocols
 $ man 2 mkdir
 /dev/tty
 $ man man
 5 Standard file formats
 /etc/hosts
 $ man -k mkdir  6 Games and demos
 Manpage sections (LAH  /usr/games/fortune
Table 1.2 @ page 12)  7 Misc. files and docs
 1 User-level cmds  man 7 locale
and apps
 /bin/mkdir
 8 System admin. Cmds
 /sbin/reboot
 2 System calls
 int mkdir(const char *, …);
 $ manpath
 3 Library calls  $ env | grep MANPATH
 int printf(const char *, …);  /etc/man.config

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Fish vs. Fishing (cont)
 Google
 linux package management -rpm
 “linux package management” -rpm
 linux OR windows
 rpm site:redhat.com
 linux faq filetype:pdf
 Info
 Text-base, menu-based help from GNU
 ?, h, u, t, ^N, ^P, Enter
 $ info info
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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 ~weesan  $ find /usr/include | grep stdio.h
 What will “cd ~/weesan” do?

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Basic Commands (cont)
 echo  rm
 $ echo “Hello World”  $ rm foo
 $ echo -n “Hello World”  $ rm -rf foo
 cat  $ rm -i foo
 $ cat /etc/motd  $ rm -- -foo
 $ cat /proc/cpuinfo  chgrp
 cp  $ chgrp bar /home/foo
 $ cp foo bar  chsh
 $ cp -a foo bar  $ chsh foo
 mv
 chfn
 $ mv foo bar
 $ chfn foo
 mkdir
 chown
 $ chown -R foo:bar /home/foo
 $ mkdir foo

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Basic Commands (cont)
 tar  Pipe
 $ tar cvfp lab1.tar lab1  $ cal > foo
 gzip  $ cat /dev/zero > foo
 $ gzip -9 lab1.tar  $ cat < /etc/passwd
 untar & ungzip  $ who | cut -d’ ‘ -f1 | sort |
 $ gzip -cd lab1.tar.gz | tar xvf – uniq | wc –l
 $ tar xvfz lab1.tar.gz  backtick
 touch  $ echo “The date is `date`”
 $ touch foo  $ echo `seq 1 10`
 $ cat /dev/null > foo  Hard, soft (symbolic) link
 ln vmlinuz-2.6.24.4 vmlinuz
 ln -s firefox-2.0.0.3 firefox

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Basic Commands (cont)
 Disk usage
 $ df -h /
 File space usage
 $ du -sxh ~/
 Advance stuff 
 $ ssh eon who
 $ ssh eon ‘cd .html ; tar cvfp - cs183 | gzip -9c’ | tar
xvfpz -
 $ ssh kilo-1 ‘tar cvfp - /extra/weesan’ | tar xvfp - -C /

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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)

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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 w/out saving)
 Deletion  ^x^s (save)
 ^d (delete one char)  ^x^w (write to a new file)
 alt-d (delete one word)
 ^k (delete line)

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Q&A

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References
 LAH
 Ch 1: Where to Start
 Unix history
 http://en.wikipedia.org/wiki/Unix
 http://upload.wikimedia.org/wikipedia/commons/7/77/Unix_
history-simple.svg
 Linus Torvalds
 http://en.wikipedia.org/wiki/Linus_Torvalds
 Linux Kernel
 http://www.kernel.org/

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References
 GNU (Gnu’s Not Unix)
 http://www.gnu.org/
 Linux Distribution
 http://en.wikipedia.org/wiki/Linux_distribution
 http://en.wikipedia.org/wiki/List_of_Linux_distributions
 PS2: Computational Cluster
 http://arrakis.ncsa.uiuc.edu/ps2/cluster.php
 Linux Gadgets
 http://linuxdevices.com/articles/AT4936596231.html
 TiVo
 http://dynamic.tivo.com/linux/linux.asp

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References
 Nintendo DS Lite
 http://www.nintendo.com/ds/

 Nokia N810
 http://www.nokia.com/

 http://www.engadget.com/2007/10/17/nokia-n810-gets-official/

 Linux Distribution
 http://en.wikipedia.org/wiki/Linux_distribution

 GNU/Linux Distro Timeline: http://futurist.se/gldt/

 http://www.distrowatch.com/

 http://www.linux.org/dist/

 Google Advance Search

 http://www.google.com/intl/en/help/refinesearch.html

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