natawut nupairojassembly language1 unix survival guide

Natawut Nupairoj Assembly Language 1

Unix Survival Guide


What is Unix ?

• Very popular OS. (Solaris, HP/UX, Ultrix, Linux, FreeBSD, etc.)

• Being used in many medium-end/high-end servers.

• Very stable, flexible, portable.


Why do you need to care ?

• Good question! It is Windows’ world anyway.• WRONG!

– A lot of servers are Unix-based.– Unix is older than Windows but yet it still has the old

basic concepts.– Unix is considered to be “cleaner” than Windows in

term of coding.– Unix is still more secured than Windows.– Most of network devices are Unix-based (e.g. routers,

caches, mail servers, security servers).– You can find a job with good pay with Unix.


Unix History

• Born in 1969 as a child of project called “Multrics” (by Bell Labs, GE, and MIT).

• Its famous parents: Ken Thompson and Dennis Ritchie.

• Its famous sibling (and supporter): C language (by Brian Kennigan and Dennis Ritchie).

• First machine: DEC’s PDP-7.• First game on Unix: “space travel”.• Famous game on early Unix: “rogue”.


Unix Features

• Why is it so popular ?– Multitasking.– Multiuser.– Portability.– Network applications.


Basic Skills for this Class

• Basic Unix operations: login, logout, directory• Basic Unix commands: man, ls, cd, pwd, rm,

mv, cat, more• Editing commands: pico, vi• Assembler / Debugger: as, ld, gcc, gdb• Which computer you can use ?

– Remote login (using telnet or secure shell).– cpu200, zeus, and athena.


Basic Unix Operations

• Start using the system: loginlogin: natawutPassword:Last login: Mon Aug 12 22:37:02 from zeus.cp.eng.chula$

• Quitting from the system: logout$ logout

• ALWAYS LOGOUT !!!– Can use “exit” or CTRL-D.


Editing Keys

• When entering a command at the shell prompt:– erase one character: ctrl-H / backspace– erase the whole line: ctrl-U– stop execution: ctrl-C– pause output to the screen: ctrl-S– resume after a pause: ctrl-Q


Directory Structure

• All files are organized in “(sub)directory” (folders).– hierarchy: current

directory, parent directory, root directory

– path reference: absolute, relative

/

home usrbin

natawut athasit

Admin bin public_html

Class Images


Basic Unix Commands

• Getting help: man (manual)$ man ls

$ man man

• format: man <command>


Basic Unix Commands (cont’)

• Listing all the files: ls$ ls

Admin Class bin public_html

• options: ls -l, ls -a, ls -al, ls <directory>$ ls –l Class

$ ls –al ..

• format: ls [-laCFR] <directory>



• Understand permissions:$ ls -ltotal 168drwxr-xr-x 3 natawut faculty 4096 Aug 5 16:24 Classdrwxr-xr-x 2 natawut faculty 4096 Jul 10 00:25 Imagesdrwxr-xr-x 2 natawut faculty 4096 Jul 10 00:25 Librarydrwxr-xr-x 8 natawut faculty 4096 Jan 26 2002 Olddrwxr-xr-x 2 natawut faculty 4096 Aug 5 16:09 Publicationsdrwxr-xr-x 2 natawut faculty 4096 Aug 1 01:04 Templates-rw-r--r-- 1 natawut faculty 4800 Aug 1 01:05 class.html-rw-r--r-- 1 natawut faculty 4551 Aug 1 01:17 contact.html-rw-r--r-- 1 natawut faculty 5817 Aug 1 01:21 home.html-rw-r--r-- 1 natawut faculty 3343 Feb 19 17:15 index.html...



• Finding out where I am: pwd (print working directory)

$ pwd

/home/natawut

• Walking around: cd (changing directory)$ cd Admin

$ pwd

/home/natawut/Admin



• change to parent directory, root directory.$ pwd

/home/natawut/Admin

$ cd ..

$ pwd

/home/natawut

$ cd /

$ pwd

/

$ cd

$ pwd

/home/natawut



• change to absolute path, relative path.$ pwd/home/natawut$ cd public_html/Class$ pwd/home/natawut/public_html/Class$ cd /usr$ pwd/usr$ cd$ pwd/home/natawut$ cd ../../usr$ pwd/usr



• Deleting stuffs: rm (remove)$ rm hw1.asm

• Changing a file’s name / Moving things around: mv (move)

$ mv hw1.asm h1.abc

$ mv h1.abc Class

$ mv h1.abc Class/hw1.txt



• Displaying file’s content: cat$ cat hw1.asm

• A better version than cat: more$ more hw1.asm


•Editing Files in Unix

• Several editing programs: pico, vi, emacs• Simple editor: pico

– Available only on cpu200.– Similar to “Notepad” program on Windows.

• For advance users: vi and emacs


References

• “man” pages.• Grace Todino et. al., Learning the UNIX

Operating System, O’Reilly&Associates, Inc.• Other Unix books.• Links in my homepage.

http://www.cp.eng.chula.ac.th/~natawut

natawut nupairojassembly language1 unix survival guide

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