UNIX Journey Workshop:

Table of Content:

1. What is UNIX?

1. What is UNIX?

• Unix is one of the first widely-used operating systems.

• Is the basis for many modern Operating systems.

• Helped set a standard for the multi-tasking multi-user systems

2. History of UNIX

• 1969 Ken Thompson, Dennis Ritchie (et al.) start working on a file system, and name their system UNICS, which is later changed to UNIX.

• 1973 Thompson and Ritchie rewrote UNIX in C (while most of the operating systems at that time were written in assembly)

• 1991 Linux, GNU, and others: similar to UNIX, but their source code rewritten, very popular and widespread, free. _{(Many Linux Distributions: Ubuntu, Fedora, Debian, ...)}

3. UNIX Architecture

3.1 Kernel:

The part manages and controls the machine and takes care of scheduling of various computer Programs

3.2 Shell:

A command interpreter that looks after the communication between the user and the system.

3.1 Programs:

various utility Programs which performs a number of tasks (editing a file, sorting numbers or drawing a plot, .....)

4. Why use UNIX?

• Allows you to accomplish and automate complicated tasks that would usually require huge manual labor.

• A rich set of small commands and utilities that can be combined in unlimited ways to perform complex custom tasks.

• It is fun!

• Not limited to preconfigured combinations or menus, as in personal computer systems.

• Extremely useful computer skill that will be relevant many years from now.

5. UNIX File system

5.1 Quick notes:

• the unix file system consists of one single global root directory that encapsulates everything of the machine. no matter how many disks or volumes are there.

• Files and directories names are case sensitive.

• The way to separate directories is with a forward slash "/".

5.2 The File system Hierarchy:

• Root : Main & parent Directory

• /home: contains all the users and the user data and files

• /dev : Access to hardware devices

• /lib : Stores the libraries

• /mnt : is used to mount disk drives

• /usr : user installed Programs and files

• /etc : system Settings

6. Basic commands:

• print working directory (pwd):

  • Prints the full path of the current directory

  • Very handy when you get lost in the directories jungle

  • A useful variable for the strings

• list *(ls) [flags] [file] * :

• Lists the content of the current directory.

common options:

' - l ' => List a detailed file/folder information.

' - lh ' => List a detailed file/folder information.

' - a ' => list hidden files.

• change directory (cd) [directory name]:

  • goes from the current directory to the specified one.

  • defaults to the home directory if not given a destination.

  • can take both absolute or relative paths.

  relative: the location of a file or a folder that beginning at the current directory.

  cd csc1101

  absolute: the location of a file or a folder starting at / _{(home directory)}

  cd /home/user1/csc1101

  shortcuts:

  ' ~ ' => Current user's home directory.

  ' . ' => The current directory.

  ' .. ' => The parent of the current directory.

  ' - ' => The previous directory.

• Make a file (touch) [flag] [file]:

  • creates a new file with the name [file]
  • Adjusts the timestamp of [file]

• Make Directory (mkdir) [flags] <directory> :

  • makes a new directory with the name

  • can use relative and absolute paths to make directories outside the current directory.

  common options:

  ' -p ' => creates parent folders as well.

• Remove File (rm) [file]