1. 40 Years and Still Rocking the Terminal!
UNIX
40 Years and Still Rocking the Terminal!

2. A Little History Developed by AT&T @ Bell Labs in 1969
Many different variants
BSD, Solaris, HP-UX, AIX
Version 7 or System V
Linux is not UNIX but a “Unix-like” system

3. The C Programming Language
Unix is “Open”
Built using
The C Programming Language
Unix is a portable, multi-tasking and multi-user operating system consisting of many small, powerful programs

4. What Makes Unix AWESOME!?
Commands, Commands, and more Commands

5. These three tools alone can do incredible things
Interpreters
The Bourne-Again Shell (BASH)
AWK
SED
These three tools alone can do incredible things

6. What is BASH BASH is an improved replacement shell
It’s also a powerful scripting language
It supports full logical expressions and looping mechanics
But its true power is it’s ability to chain together commands with pipes and redirects
Drop down a terminal and show how to make a variable, how to read a variable
How to make an if/else and if/elif/else, a for in using a `ls type`

7. Some Power Features
Pipes: cat someFile | awk ‘{ print $1 }’ - reads someFile to stdout, then redirects it as the stdin to awk
Redirection: diff file1 file2 > theDifferences - redirects all output to a file named theDifferences tidy -i an_HTML_file 2> /dev/null - redirects any errors for /dev/null (a.k.a. “the default log file”)

8. What is AWK?
“AWK is a programming language that is designed for processing text-based data, either in files or data streams”
Powerful enough to write full programs
Incredible enough to use from the terminal kill -9 `ps aux | awk -V user=$(whoami) '{ if ($1 ~ user ) print $2}'`

9. What is SED SED is a stream editor
Using regular expressions, you can edit an input stream
Most powerful when used in conjunction within a BASH script
sed ‘s/p(ython|erl)/ruby/g’ - searches for the word python or perl and replace it with ruby

10. Basic Terminal Commands
cd - Change directories
ls - Directory listing
rm - Remove a file
mkdir - Make a new directory
pwd - Print the Present Working Directory
cp - Copy a file
mv - Move or Rename a file
wc - Word or Line or Character count
cat - Concatenate multiple files
head - Output the first line of an input file
tail - Output the last line of an input file
grep - Search a file and print matching lines
vi - Complicated Text Editor (Alt is nano or pico)

11. Using the Commands...
To change a directory - cd theDirName - cd ~/levelOne/levelTwo/levelThree - cd ../
To list the contents in a directory - ls - ls -l - ls --color=”always”

12. Using the Commands...
To make a directory - mkdir theDirName - mkdir -p levelOne/levelTwo/levelThree
To search a file for a pattern - grep -E “p(ython|perl)” fileName - grep “plain text” ./
Delete a directory structure - rm -Rf ~/temp # will recursively delete everything in temp

13. Customize Your Commands
BASH allows you to customize built-in commands with the alias command
alias ls=’ls -G’
alias ll=’ls -l’
alias la=’ls -a’

14. Type the following into a Terminal
A Quick Script
Type the following into a Terminal
cat << EOF > /usr/local/bin/hunt
#!/bin/bash
find $(pwd) -name “$1” -print
EOF
chmod 755 /usr/local/bin/hunt

15. A Better Shell Prompt BASH uses a lot of environment variable
These variables are used by built-in commands and to customize BASH
PS1 is the variable BASH uses to style your first prompt (Prompt Style 1)

16. \d the date in "Weekday Month Date" format
\e an ASCII escape character (033)
\h the hostname up to the first `.'
\H the hostname
\j the number of jobs currently managed by the shell
\l the basename of the shell's terminal device name
\n newline
\r carriage return
\s the name of the shell, the basename of $0
(the portion following the final slash)
\t the current time in 24-hour HH:MM:SS format
\T the current time in 12-hour HH:MM:SS format
the current time in 12-hour am/pm format
\u the username of the current user
\v the version of bash (e.g., 2.00)
\V the release of bash, version + patchlevel
(e.g., )
\w the current working directory
\W the basename of the current working direcory
\! the history number of this command
\# the command number of this command
\$ if the effective UID is 0, a #, otherwise a $
\nnn the character corresponding to the octal number nnn
\\ a backslash
\[ begin a sequence of non-printing characters
\] end a sequence of non-printing characters

17. BASH Colors Black 0;30 Dark Gray 1;30 Blue 0;34 Light Blue 1;34
Green ; Light Green 1;32
Cyan ; Light Cyan 1;36
Red ; Light Red 1;31
Purple ; Light Purple 1;35
Brown ; Yellow ;33
Light Gray 0; White ;37

18. A Custom PS1
\e[0;31m\]\h\[\e[1;30m\]] \[\e[1;30m\]\w \n$\[\e[0m\]
Produces the following prompt