Before we start…Getting Started

UST Outline

• History• Getting Started• Basic commands (command line)• Operations on Files and Directories• Input and Output• Editors (Emacs, gedit, vi)• Processes and jobs. • Regular expressions and pattern matching. • Shell scripts (sed, awk)• Maybe Programming (perl, python)

Before we start 1

• An overview of the course. • be patient, the learning curve is steeper than

with windows, but you will develop a deeper appreciation of computers after mastering Unix.

• no viruses with Unix• many people (and companies and

governments!) are switching to Unix and Linux• You will do a lot of typing, rather than clicking

and dragging icons (maybe you should learn to touch type!).

Before we start 2

• look at the environment as you learn, and you will learn more. be observant.

• think about what you are doing.

• Unix can be thought of as not being user friendly

• Unix is in contrast to Windows.

Before we start 3

• you may love/hate Windows/Unix.

• try and develop a balance perspective.

• you can switch between operating systems.

• but you should learn to use both (why?).

• Unix offers diversity from windows.

Getting Started

• You will not know everything about Unix, part of this course is to teach you how to find it.

• You need to do Unix to learn it, not just read about it.

• You cannot learn it just from the man pages, like you cannot learn a language from a dictionary, or java from the API.

ASCII

• ASCII (American Standard Code For Information Interchange), is a numerical code for characters.

• 7 bits providing 128 characters.• Unicode has now been developed (www.unicode.org)• Unix is case sensitive.• Control characters (e.g. ^L clears the screen, ^H is

backspace, ^C cancels a login attempt)• What do ^A and ^E do?• the Unix environment is unforgiving, so be careful.

Shells

• Unix often comes with three main shells.

• Bourne and Korn shells use the dollar $ prompt. The C shell uses percent %

• You can find out your shell by echo $SHELL

• To log out type exit or logout or quit.

• Read the error messages (Just like you should be doing with Java)

Advice 1

• ^C kills a command, and ^Z suspends the command.

• Unix terminals are typically left switched on.

• keep your password secret. passwd to change your password

• keep a list of commands you have found useful during the course.

Advice 2

• use the tab key to auto-complete commands and arguments.

• semi-colon ; can connect two commands. • pipe | send output of one command to input of

next command. • man (manual) command to find out about

commands. • Windows confirms almost everything, • Unix confirms almost nothing - so be careful

(unless you use interactive mode).

Advice 3

• Always think – is there an easier way to do this (remember computing is all about efficiency)

• Always think – is there another way to do this. Often doing things a different way make you think about what you are doing.

• Always think – has someone else already solved this problem.

• Always think – can what you are doing be automated. Computer thrive on repetitive processes.

• Make a list of commands you use (along with the options)