Programming and problem solving 3

PROGRAMMING AND PROBLEM SOLVINGASSIGNMENT - 1

LINUX OPERATING SYSTEM

TEAM X.P AAHLAD SUSHRUTH GANESH VIJAY VINAY

PRESENTED BY

What is an operating system ?

A: An Operating System is a computer program that manages the resources of a computer. It accepts keyboard or mouse inputs from users and displays the results of the actions and allows the user to run applications, or communicate with other computers via networked connections. Briefly, it can be defined as the interface between the user and the computer

Introduction to operating system

There are many operating systems in this world. Some of them are as given below : Windows MAC OS Solaris Linux knoppix Fedora Android Power DOS and etc…….

Different operating systems in the world

What is Unix/Linux? History of Linux Features Supported Under Linux The future of Linux Advantages of Linux over other operating systems

OVERVIEW

What is unix/linux…..?

Linux was originally developed as a free operating system for Intel x86-based personal computers. It has since been ported to more computer hardware platforms than any other operating system. It is a leading operating system on servers and other big iron systems such as mainframe computers and supercomputers.

Today more than 90% of the world’s fastest 500 supercomputers run some variant of the linux, including the 10 fastest. Linux also runs on embedded systems such as mobile phones tablet computers, network routers, building automation controls, televisions and video game consoles. The android system which is wide in use on mobile devices is built on linux kernel………

History of Linux(i) Before Linux

• In 80’s, Microsoft’s DOS was the dominated OS for PC

• Apple MAC was better, but expensive

• UNIX was much better, but much, much more expensive. Only for minicomputer for commercial applications

• People was looking for a UNIX based system, which is cheaper and can run on PC

• Both DOS, MAC and UNIX were proprietary, i.e., the source code of their kernel is protected

• No modification is possible without paying high license fees

The Unix operating system was conceived and implemented in 1969 at AT&T's Bell Laboratories in the United States by Ken Thompson, Dennis Ritchie, Douglas McIlroy , and Joe Ossanna. It was first released in 1971 and was initially entirely written in assembly language, a common practice at the time. Later, in a key pioneering approach in 1973, Unix was re-written in the programming language C by Dennis Ritchie (with exceptions to the kernel and I/O).

The availability of an operating system written in a high-level language allowed easier portability to different computer platforms. With a legal glitch forcing AT&T to license the operating system's source code to anyone who asked, Unix quickly grew and became widely adopted by academic institutions and businesses. In 1984, AT&T divested itself of Bell Labs. Free of the legal glitch requiring free licensing, Bell Labs began selling Unix as a proprietary product

History of Linux(ii) Development of linux

Ken thompson & dennis ritchie

Linux has been used for many computing platforms like PC, PDA, Supercomputer,…

Not only character user interface but graphical user interface is available

Commercial vendors moved in Linux itself to provide freely distributed code. They make their money by compiling up various software and gathering them in a distributable format

Red Hat, Slackware, etc

Linux today

About linux osLinux kernel

Shell interprets the command and request service from kernel Similar to DOS but DOS has only one set of interface while Linux can select

different shell Bourne Again shell (Bash), TC shell (Tcsh), Z shell (Zsh) Different shell has similar but different functionality Bash is the default for Linux Graphical user interface of Linux is in fact an application program

work on the shellBash,Tcsh,Zsh

File management

Directory tree

When you log on the Linux OS using your username you are automatically located in your home directory

( root)

The most important subdirectories inside the root directory are

/bin : Important Linux commands available to the average user.

/boot : The files necessary for the system to boot. Not all Linux distributions use this one. Fedora does.

/dev : All device drivers. Device drivers are the files that your Linux system uses to talk to your hardware. For example, there's a file in the /dev directory for your particular make and model of monitor, and all of your Linux computer's communications with the monitor go through that file.

/etc : System configuration files.

/home : Every user except root gets her own folder in here, named for her login account. So, the user who logs in with linda has the directory /home/linda, where all of her personal files are kept.

/lib : System libraries. Libraries are just bunches of programming code that the programs on your system use to get things done.

The most important subdirectories inside the root directory are

/mnt : Mount points. When you temporarily load the contents of a CD-ROM or USB drive, you typically use a special name under /mnt. For example, many distributions (including Fedora) come, by default, with the directory /mnt/cdrom, which is where your CD-ROM drive's contents are made accessible.

/root : The root user's home directory.

/sbin : Essential commands that are only for the system administrator.

/tmp : Temporary files and storage space. Don't put anything in here that you want to keep. Most Linux distributions (including Fedora) are set up to delete any file that's been in this directory longer than three days.

/usr : Programs and data that can be shared across many systems and don't need to be changed.

/var : Data that changes constantly (log files that contain information about what's happening on your system, data on its way to the printer, and so on).

Commands : - / - (root directory). /root - home directory of user root. pwd - you can see your home directory. df - to check the disk space available. cd - to change directory or to go to one. .. - to move to parent directory. ls - lists content of a directory. cp - copy one file to another. rm - to remove a file. man - ask for manual of a command. cat - to show context of a text file..

Important commands

PRO’s : -

Runs on just about any hardware Linux actually has the broadest driver support of any

system More options than any other system. If you want to change anything in Linux you can. The only

limiting factor is your desire to figure out how. Way more secure than Windows XP and even OSX. Full access to the free open source library of software. Great

full featured, compatible, and free replacements for your proprietary software.

Linux management, for example patch management, is much easier. Typical one command or wizard has to be invoked in order to update everything

About linux os

Con’s : -

The latest and greatest hardware is typically slower to reach Linux.

The shear number of options can be daunting to a non-technical user. 

Limited support for proprietary applications.

About linux os

LINUX VS WINDOWS - I

LINUX WINDOWS

Linux kernel is developed by the community programmers of AT&T BELL LABORATORIES

Linux can be freely distributed, downloaded freely. There are priced versions for Linux also, but they are normally cheaper than Windows.

Linux can be installed on a wide variety of computer hardware, ranging from mobile phones, tablet computers and video game consoles, to mainframes and supercomputers.

Microsoft corporation created the Windows operating system.

For desktop or home use, Windows can be expensive. A single copy can cost around $50 to $ 450 depending on the version of Windows.

On PC's desktops, laptops, servers and some phones.

LINUX VS WINDOWS - II

LINUX WINDOWS Supported file systems are

Ext2, Ext3, Ext4, Jfs, ReiserFS, Xfs, Btrfs, FAT, FAT32, NTFS

Linux has had about 60-100 viruses listed till date. None of them actively spreading nowadays.

In case of Linux, threat detection and solution is very fast, as Linux is mainly community driven and whenever any Linux user posts any kind of threat, several developers start working on it from different parts of the world

Supported file systems are FAT, FAT32, NTFS, exFAT

According to Dr. Nic Peeling and Dr Julian Satchell's “Analysis of the Impact of Open Source Software” there have been more than 60,000 viruses in Windows

After detecting a major threat in Windows OS, Microsoft generally releases a patch that can fix the problem and it can take more than 2/3 months. Sometimes sooner, Microsoft releases patches and updates weekly.

Mac os vs linux

Linux vs mac OS - ILINUX MAC OS

Linux kernel is developed by the community programmers of AT&T BELL LABORATORIES

Linux can be freely distributed, downloaded freely. There are priced versions for Linux also, but they are very cheaper than MAC’s

Linux can be installed on a wide variety of computer hardware, ranging from mobile phones, tablet computers and video game consoles, to mainframes and supercomputers

Mac os is developed and distributed by Apple, Inc.

Not available for free, except in their own manufactured PC’s.Computers start at $599 for the Mac Mini, and $999 for the Macbook Air.For desktop or home use Macs are more expensive than a PC.

Cannot be installed on any hardware.MAC os is only available on the platforms released by the APPLE INC.

Linux vs mac OS - IILinux MAC os

Supported file systems are Ext2, Ext3, Ext4, Jfs, ReiserFS, Xfs, Btrfs, FAT, FAT32, NTFS

Linux has had about 60-100 viruses listed till date. None of them actively spreading nowadays

In case of Linux, threat detection and solution is very fast, as Linux is mainly community driven and whenever any Linux user posts any kind of threat, several developers start working on it from different parts of the world

Supported file systems are HFS+, NTFS,FAT32, Ext2,exFAT.

31 viruses have been detected to affect Mac OS. Roughly half of these cause little to no damage.virus attacks in MAC are very rare.

Threats in MAC’s are very rare as every programme used in the system must and should be the one one verified by APPLE Inc. and the corporation makes sure each and every programme is 100% safe for the user

SIDE - BY - SIDE COMPARISION OF APPLE , WINDOWS , LINUX OPERATING SYSTEMS

why use linux than other operating systems..?

The best feature of Linux operating systems is its low susceptibility to virus and malware infestation. If you have been a Windows user for a long time, you would know how problematic Windows is when it comes to viruses. With Linux, you are spared from all the hassle of having to constantly update your anti-virus software or scan your computer every so often. Linux is almost always a free operating system with multiple sources distribution. In contrast, Windows and Mac OS X are some of the most expensive operating systems available. If you want to cut on costs, you can definitely benefit from choosing Linux for your everyday needs.

Linux is an open source platforms with plenty of developers working on applications, functions, features and add-ons that are guaranteed to improve your user experience. Contrary to popular belief, many Linux functions rival those of Windows and Mac OS. All that you need to do is try it out for a couple of weeks to personally see for yourself how Linux is so much better than many perceive it to be. One of the most important reasons why computer-savvy individuals consider Linux as the best operating system is because it is far more customizable than its popular counterparts. With Windows and Mac, there are plenty of restrictions that limit what you can do to the OS. This is not easily noticeable to the average computer user but if you are planning to do plenty of customizations, Linux is undoubtedly the best operating system for this purpose.

If you do not want to ditch your Windows applications but would want to give Linux a try, there are many compatibility programs that allow Linux to run Windows programs like Word, Excel, and PowerPoint. You can run programs like Wine to load Microsoft Office programs and still enjoy the many benefits of Linux as the underlying operating system Low resource requirements. Ever notice how Windows hangs up after a few years of use? As your computer gets older, it demands more resources such as RAM eventually slowing down your system. With Linux’s low-resource approach, you are less likely to encounter slower load times. These reasons highlight the versatility and strength of Linux operating systems and easily explain why it is the best operating system on the market.

THE END