Introduction to the Linux Operating System Objectives
In this lesson, you will learn to: ☛ Identify the functions of an operating system ☛ Differentiate between single- and multi-
operating systems
☛ Identify the inception, growth, features, and
architecture of Linux
☛ Identify the various shells available in Linux
☛ Start a Linux session ☛ List the s who are currently logged in
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Introduction to the Linux Operating System Objectives(contd.) ☛ Assign s to a Linux using the wd command ☛ End a Linux session ☛ Identify the features of the Linux filesystem ☛ Create a directory using the mkdir command ☛ Delete a directory using the rmdir command ☛ List the contents of a directory using the ls command ☛ Copy a file using the command
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Introduction to the Linux Operating System Objectives(contd.) ☛ Move a file using the mv command ☛ Delete a file using the rm command ☛ Use man command to get online help
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Introduction to the Linux Operating System Getting Started ☛ Operating Systems ✓ An operating system (OS) is a software program that acts as an interface between a and a computer, e.g Linux, Unix, Microsoft DOS etc ☛ Functions of an Operating System ✓ Command Interpretation ✓ Process Management ✓ Memory Management ✓ I/O Operations and Peripheral Management ✓ File management ©NIIT
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Introduction to the Linux Operating System Getting Started(contd.) ☛ Types Of Systems ✓ Single- Systems ➤A
single- system was designed for use by one person at a time. A personal computer (PC) is a popular single- system
✓ Single– Operating Systems ➤ MS
DOS (Disk Operating System) is an example of a single- operating system
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Introduction to the Linux Operating System Getting Started(contd.) ☛ Types Of Systems(contd.) ✓ Multi- Systems ➤ More
than one can work simultaneously on a multi- system
Printer
Communication Lines
Multi- System
System Console
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System Unit -Processor -Disk(s) -Tape(s) -Floppy Disk(s)
Graphical or text Terminals
Remote Terminals
Linux/Lesson 1/Slide 6 of 32
Introduction to the Linux Operating System Getting Started(contd.) ☛ Types Of Systems(contd.) ✓ Multi– Operating Systems ➤ Linux,
Unix, and Windows NT Terminal Server are examples of multi- operating systems
➤ More
than one can connect to the system and work concurrently at any point in time
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Linux/Lesson 1/Slide 7 of 32
Introduction to the Linux Operating System Flavours of Linux Distributor Name
Website
☛ Red Hat
http://www.redhat.com
☛ Caldera
http://www.caldera.com
☛ Mandrake
http://www.linux-mandrake.com
☛ Debian
http://www.debian.org
☛ SuSE
http://www.suse.com
☛ Slackware
http://www.slackware.com
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Introduction to the Linux Operating System The Linux Architecture The Linux operating system consists of the following: ☛ Kernel ☛ Shell ☛ Utilities and Application Programs
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Introduction to the Linux Operating System Shells Available in Linux ☛ Bourne Shell (sh) ☛ C Shell (csh) ☛ Korn Shell (ksh) ☛ Restricted Shell (rsh) ☛ Bash Shell (bash) ☛ Tcsh Shell (tcsh) ☛ A Shell (ash) ☛ Z Shell (zsh)
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Introduction to the Linux Operating System Starting a Linux Session: Logging on ☛ Connect to a computer running the Linux operating system from any other computer using the telnet program telnet
☛ The assigns each a HOME directory when a new logon is created. When you log on, you are taken directly to your HOME directory
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Introduction to the Linux Operating System Listing the s Currently Logged In ☛ A list of s who are currently logged in can be found by using the who command who [options]
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Introduction to the Linux Operating System Security for the s: s ☛ Linux provides an additional measure of security by allowing you to have a associated with your name ☛ The combination of the name and is checked by Linux to if it is an authorized
Changing the ☛ s can be changed using the wd command ☛ The wd command asks for the old to ensure that only the authorized is trying to change the ©NIIT
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Introduction to the Linux Operating System Root : ☛ The root (also known as the super) is the of the Linux operating system
Ending a Linux Session: Logging out ☛ Typing exit or at the command prompt ends your current Linux session. You can also press
+d to end the Linux session
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Linux/Lesson 1/Slide 14 of 32
Introduction to the Linux Operating System The Linux Filesystem /
bin cat
ch m od
boot
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etc
usr
dev
ls tom
Desktop
De fa ul t
home
Templates
michael
pr og ra m 1
3
pr og ra m 2
Legend
St ar t
Directory File
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Introduction to the Linux Operating System The Linux Filesystem (contd.) ☛ The /bin directory stores many utilities of Linux ☛ The /dev directory stores all the device-related files for the system ☛ The /etc directory stores the operating system-related data which s and the operating system need to refer to, such as the wd file ☛ The /lib directory contains libraries of data for the compilers installed in the Linux operating system, for example, the C language routines ☛ The /home directory generally contains all the HOME directories of s
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Introduction to the Linux Operating System The Linux Filesystem (contd.) ☛ The /usr directory stores the operating system files that are not involved in the boot process ☛ The /var directory has information specific to different utilities of Linux
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Introduction to the Linux Operating System In Linux, File Names: ☛ Can be up to 256 characters long ☛ Can contain special characters, except for ‘/’ ☛ Can contain both uppercase and lowercase letters of alphabets ☛ Are case-sensitive ☛ Should not have a blank or a tab
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Introduction to the Linux Operating System Types of Files in Linux File Types
Ordinary files
Character Device files
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Directory files
Block Device files
Special files
Hard links
Symbolic links
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Introduction to the Linux Operating System Types of s in Linux ☛ System ✓ A System (SA) is primarily responsible for the smooth operation of the Linux operating system ☛ File Owner ✓ The who creates a file is said to be its owner ☛ Group Owner ✓ A group of s is also given a name, just as a is given a name ☛ Other s ✓ These are s who do not belong to a particular group ©NIIT
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Introduction to the Linux Operating System Directory Commands in Linux ☛ Identifying the Current Directory Path ✓ The pwd (print working directory) command is used to display the full path name of the current directory ☛ Changing the Current Directory ✓ The cd (change directory) command changes the current directory to the directory specified ☛ Creating a Directory ✓ The mkdir (make directory) command is used to create directories ©NIIT
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Introduction to the Linux Operating System Directory Commands in Linux (contd.) ☛ Removing a Directory ✓ The rmdir (remove directory) command removes the directory specified ☛ Listing the Contents of a Directory ✓ The ls command is used to display the names of the files and sub-directories in a directory
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Introduction to the Linux Operating System File Commands in Linux ☛ The cat (concatenate) command displays the contents of the specified file ☛ Copying Files ✓ The (copy) command duplicates the contents of the source file into a target file ✓ [options] <source file/s> <destination directory/file> ☛ Removing Files ✓ The rm (remove) command is used to delete files or directories ✓ rm [options] file/s ©NIIT
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Introduction to the Linux Operating System File Commands in Linux (contd.) ☛ Moving and Renaming Files ✓ The mv (move) command is used to move a file or directory from one location to another or to change its name ✓ mv [option] source destination ☛ Displaying the Contents Page–Wise ✓ The more command is used to display data one screen-full at a time. While viewing a file using the more command, once you have scrolled down, you cannot move up ✓ more [options]
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Introduction to the Linux Operating System File Commands in Linux (contd.) ☛ Displaying the Contents Page–Wise (contd.) ✓ The less command is similar to the more command except that you can scroll upwards also while viewing the contents of a file ✓ less [options]
Wildcard Characters ☛ The shell offers the facility to perform an operation on a set of files by the use of certain special characters in the command in place of the actual file names
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Introduction to the Linux Operating System File Commands in Linux (contd.) Wildcard Characters (contd.) ☛ The * Wildcard ✓ The * wildcard is interpreted as a string of none, one, or more characters ☛ The ? Wildcard ✓ The ? wildcard matches exactly one occurrence of any character ☛ The [ ] Wildcard ✓ The [ ] wildcard can be used to restrict the characters to be matched ©NIIT
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Introduction to the Linux Operating System Getting Online Help ☛ The man command is used to get online help to a about the various options for any command in Linux ✓ man
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Introduction to the Linux Operating System Summary In this lesson you learned that: ☛ An operating system has the following functions: ✓ Command Interpretation ✓ Process Management ✓ Memory Management ✓ I/O Operations and Peripheral Management ✓ File Management ☛ A single- system is designed for use by one person at a time ☛ More than one can work simultaneously on a multi- system ©NIIT
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Introduction to the Linux Operating System Summary(contd.) ☛ The Linux operating system consists of kernel, shell, utilities, and application programs ☛ Some of the commonly available shells in Linux along with their executable file names are: ✓ The Bourne shell (sh) ✓ the C shell (csh) ✓ The Korn shell (ksh) ✓ The Restricted shell (rsh) ✓ The Bash shell (bash) ✓ The Tcsh shell (csh/tcsh) ©NIIT
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Introduction to the Linux Operating System Summary(contd.) ✓ The A shell (ash) ✓ The Z shell (zsh) ☛ The telnet command is used to connect to a Linux server ☛ The wd command is used to change the of the ☛ For organizing data on the disk, Linux provides a filesystem which allows you to group files in a convenient manner. The Linux filesystem has a hierarchical structure and files can be stored under directories
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Introduction to the Linux Operating System Summary(contd.) ☛ In Linux, there are three categories of files: ✓ Ordinary files ✓
Directory files
✓
Special files
☛ The types of s in Linux are: ✓ System ✓
File owner
✓
Group owner
✓
Other s
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Introduction to the Linux Operating System Summary(contd.) ☛ In Linux, chat and e-mail programs are used to communicate with each other.
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