Linux Seminarby noname

Operating System?

• System SW• Manage HW resources• Provide a platform for applications

• Windows, Linux, Mac OS, iOS, Android, DOS, …

Linux?

• OS• Made by Linus Torvalds• Inspired by Unix

• Debian, CentOS, Ubuntu, Fedora, Redhat Linux, Gentoo, Arch, Suse, Slackware, Mandriva, PintOS, …

Why do we use Linux?

• Custom• Free (in some sense)• Open source• Supports multiple users• Has compatibility with Unix-like OSs

User & Group

• Normal users• Root• Sudoers

• In SPARCS?• presparcs group• sparcs group• wheel group

File & Directory

• Actually, both of them are files

• Directory contains files

• If filename starts with ‘.’• Hidden

• .• ..

Permission

File Directory

Read Read the file See the list of files in the directory

Write Write to the fileCreate the file, Delete the file, or Rename the file in

the directory

eXecute Execute the file Get into the directory

Permission

• Three permission levels for each file• Owner(User)• Owner(Group)• Others

• Slice it!• rwxrwxrwx• r-xr--rw-

Directory Structure

• Tree structure

• /• /home• /home/noname• /etc• /root• /bin• ~/• ~noname/• ~/public_html/• …

Path

• Absolute path• /usr/bin/python• /usr/local/lib/python2.6/dist-packages/django/

• Relative path• public_html/crazy.png

• Working directory

Interface

• GUI• Gnome, KDE, …

• CUI• Terminal

Shell

• Some kind of command line on terminal• Interacts with users

• bash, sh, tcsh, ash, zsh, rc, …• bashrc

ssh

• Secure Shell• Protocol (in some cases, a program)• Default port number for ssh is 22• Opens terminal

Putty

• Program• Supports connection via ssh/telnet• Simple & Easy, but convenient

• Google ‘putty’• or http://www.chiark.greenend.org.uk/~sgtatham/putty/

Putty

Putty

Putty

Commands

• Basic Format• [command] [arg1] [arg2] …

Commands

• ls• ls [path]• ls –a• ls –l• ls –al• ls –a –l• ls -lh

• cd• cd [path]

Commands

• pwd

• rm [path]• rm –f [path]• rm –r [path]• rm –rf [path]• rm –rf /

Commands

• mkdir [path]

• rmdir [path]

• cat [path1] [path2] …• cat –n [path1] [path2] …

Commands

• cp [source1] [source2] [source3] … [destination]• cp -r [source1] [source2] [source3] … [destination]

• mv [source1] [source2] [source3] … [destination]

Commands

• more [path]• less [path]

• less > more

Commands

• passwd• passwd [username]

• ps• ps aux

• top

Commands

• wget [URL]

• ssh sparcs.org• ssh noname@sparcs.org

• scp noname@sparcs.org:~/public_html/siva.png ./kill/• scp –r ./kill/ root@bit.sparcs.org:~/

Commands

• wc [path1] [path2] …

• grep [word] [path]• grep 대한 애국가 .txt• grep –R [word] [path]

• egrep

Commands

• chmod 744 [path]• chmod 512 [path]• chmod –R 777 [path]

Commands

• tar –zxvf [path]• tar –zcvf [destination] [path1] [path2] …• tar –xvf [path]• tar –cvf [destination] [path1] [path2] …

Commands

• df• df -h

• kill [pid]

Commands

• man [command]

Commands

• E way edo jonna manayo

• ln, chown, su, sudo, fg, bg, jobs, echo, export, killall, skill, nohup, shutdown, reboot, wall, yes, chsh, man, apropos, umask, chroot, clear, …

Wildcard Character

• ? for one character• * for undecided number of characters

• It works for all matching files

Pipe & Redirection

• [command1] | [command2] | [command3] | …• ls –al | egrep ‘^d’• ls –al | egrep ‘^d’ | wc

• [command] > [path]• [command] < [path]• [command] >> [path]• [command] 2> [path]

Techniques

• !foobar…• Ctrl + r• Ctrl + d• Ctrl + l• Ctrl + a• Ctrl + e• Ctrl + u• Ctrl + c• Ctrl + z• Ctrl + \

Putty Techniques

• Mouse drag• Mouse right click• Duplicate Session• Change Settings• Special Command

Etc..

• setuid, setgid, sticky bit, environment varilables, signal, …