Types of Computer Virus

Program Viruses: These infect the executable files and are loaded in memory during the execution, taking the virus along. The virus gets active in memory, forming copies and getting files infected.

Boot Virus: This one is a computer virus that usually infects the boot sector on floppy disks, hard disks, and supposedly also the other bootable media like DVD or CD. As soon as the infected PC boots the virus attacks floppies and other types of media when they are used. Boot viruses are not common these days because floppy disks are not used much.

Multipartite Viruses: Also called multi-part virus, these types of viruses attempt to attack both the executable, or program files and the boot sector concurrently. When virus attaches to boot sector, it will in turn affect the PC’s files, and when the virus bonds to files, it will attack the boot sector. This virus can infect a system again and again if all parts of the virus are not wiped out.

Stealth Viruses: These types of viruses use certain techniques to dodge detection. They might redirect the disk head to read another sector rather than the one where they reside or they may modify the reading of the size of infected file shown in the directory listing.

Polymorphic Viruses: Polymorphism means “several forms”. A basic example for this in programming is function overloading. A polymorphic virus usually uses a polymorphic code, that is, the program uses an intricate algorithm to change the makeup of the internal code whilst maintaining its core function.

Macro Viruses: A macro virus is a new one among the types of computer virus, and infects the macros within a template. When you unlock a spreadsheet or word processing document, the macro virus gets into Normal template. Each document you open points to Normal template, and therefore gets infected with the macro virus. As this virus attaches itself to documents, the attack can spread if the docs are opened using another PC.

This is just a quick glance on types of computer virus. There are a lot of more specialized types. However this info is sufficient for the common user to be more prepared to protect the PC.

Related posts:

1. Choosing an Antivirus for Linux
2. MkCDrec_v0.7.5_utils
3. RIPLinux

Lenovo 3000 N100 TY059TK comes with Intel Core Duo Processor (T2400) clocked at 1.8 GHz. It is a notebook with 1024MB DDR2 memory and 100 Gb 5400 Rpm hard disk. The other hardware properties of this model are the following:
NVIDIA Geforce 7300 graphics card
15.4 WSXGA VibrantView Bright (1680*1050)
Multi DVD±RW
Fingerprint-reader
BlueTooth
Webcam
Wireless
3 USB – VGA – IEEE 1394 TV OU

Pardus Installation
Speaking about Pardus Installation, all you need here is the standard installation. In addition, if you want to enjoy HD resolution and to have 3D support, in this case it is necessary to set-up Nvidia drivers. The Audio Card is running out-of-box easily. Internal microphone can be switched on through KMix > Mic/Int.Mic.

Related posts:

1. Linux ThinkPad
2. How To Choose A Netbook With Linux
3. Pardus 2009.2 Geronticus eremita

From time to time Ubuntu may seem somewhat buggy. It may happen in case when you want to get drivers for wireless internet. This process may appear to be a little bit difficult. However there are numerous forums on the Ubuntu website at your disposal. Thus you can ask any question concerning the Ubuntu you are interested in. It should be noted that any Linux version disposes of this issue, however Ubuntu is the best rated one. You can retain Microsoft OS, however make certain you have enough space on your hard drive disk: 1/2 for Vista & 1/2 for Linux OS.

If you make a decision on availing yourself of Ubuntu, first you should go to www.ubuntu.com. Here you can download the ISO. Thereafter you should burn it to a CD and place it into CD/DVD drive. You will be prompted to install the version in question. You will have two options: the first option presupposes installing it along side your functional OS so you will receive a dual-boot system, the second option means formatting the hard drive and installing the new OS.

Related posts:

1. Ubuntu Notebook
2. Kiwi Linux 10.08
3. Sabily 10.10

There are several series of ThinkPad. Each model is distinguished by gently different architecture. However, there are a number of ThinkPad models that can not be used for running Linux. The article provides some of the models that are suited for Linux.

ThinkPad 340:
This monochrome-only device is distinguished by a 486SLC processor at 50 MHz. It is supplied with disks whose capacity makes up 200-360 Mb, depending on the model. David N Turner lets us know of good set-up of Slackware 2.3.0 on a 340CSE which has 12 Mb memory and 200 Mb hard disk. However David N Turner notifies that you may come across the same floppy disk change problem as the 750 models devices.

Ps/Note E35
Jerome Kaidor notifies that he has managed to make Linux 1.2.0 work on his Ps/Note E35, which he considers is substantially a ThinkPad 350 without PCMCIA slots. He succeeded in compressing everything he required into 21 Mb, even X having installed.

ThinkPad 360
This model includes options which are aimed at the 486 DX2 at 50 MHz. The disk options vary between 340 and 810 Mb. There are also dual-scan color and active-matrix screens. Linux is perfectly suited for this model according to the words of Richard Soderberg.

ThinkPad 370
Anders Odgaard informs about successful set-up on he 370C, which is similar to the 755 model. Particularly:
“Slackware Linux 2.1.0 was used. Initial booting was done with the `bare’ bootdisk, and I used the `color144′ rootdisk. At the boot prompt one must write
mount floppy=thinkpad”.

ThinkPad 701:
This model is characterized by the attractive fold-out keyboard and by modernized TrackPoint “joystick. The screen options are based around dual-scan passive and active matrix options. The disk capacity varies from 360 to 720 Mb. The processor of this model can be either the 50 MHz Intel 486DX2 or the 75 MHz 486DX4.

Related posts:

1. Lenovo Linux Laptops
2. Best Linux Operating System for Laptop
3. Moblin 2.1

Ubuntu is distributed free of charge, including corporate versions and safety renovation. Ubuntu enjoys support of Canonical Ltd. and hundreds of companies throughout the world.
The disks with Ubuntu contain only free software. It is noteworthy that the free usage, distribution, improvement of free software has been encouraged.

At present there also Ubuntu Netbook Remix has appeared which represents a system specially designed for notebooks with small screens. The Canonical Company has announced the operating system Ubuntu Netbook Remix officially for devices with smaller screens, controlled by new processors Intel atom. As concerns Netbooks, they represent mini notebooks, such as ASUS eeePC. Such notebooks are very compact and they are mainly used for Internet browsing.

Ubuntu Netbook Remix is based on Ubuntu 8.04 Hardy Heron. Its main innovation is updated interface which is used for application start, which enables to obtain quick access to files located on the small screen of a notebook. Ubuntu Netbook Remix is usually accessible to OEM suppliers because the given version includes some of the proprietary codecs and technologies.

The Ubuntu packages contain the following options: go-home-applet, Window-picker-applet, maximus, human-netbook-theme, ume-launcher, desktop-switcher.

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1. Ubuntu Rescue Remix Version 10.10
2. Ubuntu 10.10
3. Ubuntu Christian Version 5

At the moment there is no other way to use this service than getting an invitation code. I will post my opinion here as soon as I understand what to do with Wave. I am interested in Project management using Google Wave, so if you have any ideas, please, share.

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1. Free Software Foundation Activity
2. Free Software: How Did it Appear
3. Pyramid 1.0b6

Most likely the great majority of you are familiar with Windows Search Function that is pretty easy to use. In fact all Linux distributions have such an option (a graphical one) as well, so you won’t lack any functionality. However if you want to be able to find absolutely everything you need, it’s better to choose command line that has some really powerful tools to use.

In the given post we are going to review some of these tools in detail. Nevertheless it should be emphasized that there is no need to worry even if you don’t really like using command line, because no scripts or complex expressions will be discussed – just easy and understandable methods.

First of all we need to define common types of search requests. Here are the most important ones:

• Search by file name or mask (this type also includes file searching according to a certain path and exclusion of a particular path from the search)
• Search by file type (extension)
• Search by file access/creation/modification date/time
• Search by file size
• Search by file owner and access permissions
• Search of system and executable files

As far as the commands used to find files are concerned there are four of them to be reviewed:

1) find

This command is considered to be the most powerful one. It checks the file system in real time based on certain criteria. That means you will always get the most up-to-date results without the necessity to update a database. Of course, you can perform all sorts of operations on the files that were found. In addition to that is should be emphasized that file command allows you to check temp folders as well (in comparison with locate command).

However due to the fact that file command does search through the file system hierarchy, it’s considerably slower than other commands. That’s why it’s recommended to narrow your search (of course, if there is such a possibility) by searching in certain directories.

2) locate

The locate command uses a database (instead of file system itself) for searching, so it’s significantly faster than file command. However using database means that the database has to be updated in order to ensure proper search results (all new files have to be included and deleted ones mustn’t be considered). Once your database is updated you are ready to search. To update the database the only thing you should do is to run the following command:

updatedb

Taking into consideration the fact that many users may forget to update the database each and every time, it’s recommended to set up a cron job for that purpose. Here you can learn more about the cron.

3) whereis

Given command is useful in case you need to find source, binary and/or executable files which are associated with manual pages. As a return of this command you get the path.

Let’s check an example. Suppose that you need to find out where Firefox is installed. Here is what you enter and what you get:

whereis firefox

firefox: /usr/bin/firefox /etc/firefox.cfg

4) which

The which command being pretty simple is very similar to the previous one (whereis command) but it shows you the full path of shell commands instead.

It’s very useful for finding out “which” binary the system would execute if you typed the command out. Since some programs have multiple versions installed the which command comes in handy to tell you which version it is using and where it is located.

For now let’s take a closer look at each of the above mentioned commands as far as their usage is concerned.

Command Line – find

As it was mentioned before the find command is one of the best ways to search files in Linux because it has a great deal of parameters, which make it extremely easy to find the files you need. Still it should be mentioned that in most cases the usage of this powerful command is limited to the basic parameters. Of course, you can find almost everything using just those basic parameters, but you should understand that you lose much more if you don’t learn all about find tool.

Nevertheless it’s not an easy task because the syntax of this command is pretty difficult. Thus in this case you should choose between power and simplicity. If you really need the power of find tool, let’s check its potential.

In fact the best way to learn how you can use find command is to go through a lot of different examples. We will start from the easiest till more complicated ones.

File name

1. find -name 'form.html'

- name: means that the attribute is the file name
- ‘form.html’: entered text must be found.
(!) Always enclose the filename in single quotes (!)

Thus this case the system would search for a file named form.html in the current directory and any subdirectory.

In fact Current directory can be denoted in two different ways:

find 
find .

2. find / -name 'form.jpg'

Here the system would search for any file named form.jpg on the root and all subdirectories from the root.

(!) If you root as the starting point for a find command, your system can be slowed down significantly. However in case you really must run such a command, it would be better run it during low-use time or overnight. In order to make it easier for you to get familiar with the results you can redirect the output to a file using the following syntax:

find / -name '*.jpg' > allimages.out

3. find /home/fred -name 'index*'

The system would search for files having the letters index as the beginning of the file name in the directory /home/fred and its subdirectories as well.

(!) If you have some doubts about the case of the filename, there is a way not to consider it – use –iname instead of –name. So all files starting with any combination of letters in upper and lower case such as INDEX or indEX or index would be found. However in this case it will be slower, because case insensitive search takes more time (!)

4. find /usr /home /tmp -name "*.png"

As you can see in this example there is a possibility to specify more than one starting directory in a search string. Thus the system would search for a png file in user, home, temp directories and their subdirectories.

5. find . -path '/files' -prune -o -name "*.jpg"

-path: means that the attribute is the directory (path)
-prune -o: used to exclude files or directories from search

In this case the system would search for jpg files in the current directory and its subdirectories excluding files directory.

6. find /usr /home -name "*.jar" 2>/dev/null

If you need to search files in a certain directory, there is a possibility that you will get some errors due to the lack of permissions. Such errors can make it hard to find the line (search result) you need. To prevent them (errors) from appearing you need to use the above mentioned parameter.

- 2>/dev/null: given parameter is not related to find tool as such. “2″ indicates the error stream in Linux, and /dev/null is the device where anything you send simply disappears. So 2>/dev/null sends all error messages to the null file, thereby providing cleaner output.

(!) There is one more thing you can do – replace 2>/dev/null with 2>error.txt. If you use the last parameter after the search you would have a file named error.txt in a proper directory with all the error messages in it (!)

File size

7. find /music -name '*.mp3' -size +3000k

The system would search for any mp3 files that have a size more than 3000 Kilobytes (>3MB) within music directory and its subdirectories.

(!) If you would like to search for files that are, for example, less than 3000 Kilobytes, just use “-3000″ instead of “+3000″ (!)

File type

8. find /music –type d

In this case the system searches for file type. The command would find all the subdirectories in music directory.

Here are some other file type that find command can locate:

- b – block (buffered) special
- c – character (unbuffered) special
- l – symbolic link
- p – named pipe (FIFO)
- s – socket

Finding time

9. find . -mtime -1

The system would find all the files modified within the last hour in current director.

(!) It should be mentioned that there are three time stamps:

• mtime – the time that the contents of a file were last modified
• atime – the time that a file was read or accessed
• ctime – the time that a file’s status was changed

Each of these time options is used with a value n, which is specified as -n, n, or +n.

• -n returns less than n
• +n returns greater than n
• n returns exactly n matches (!)

10. find . -mtime 1

In this case the system has to find all the files that were modified exactly one hour ago in the current directory. As you understand such a command may not return any results.

11. find . -mtime +1

The system will search for files that were modified more than an hour ago in the current directory.

12. find . -amin -5

The system would find all the files modified within the last 5 minutes in current director.

Executing files

13. find / - name 'screenshot*' -exec ls -l {\}\ \;

- exec: a very important feature that allows you to execute a particular command on the results of the find command.
- ls –l: the command you want to execute
- {\}\: an indicator that the filenames returned by the search should be substituted here
- \: is the terminating string, and is required at the end of the command

Using Boolean operators

14. find /music -name 'Nirvana*' -and -size +5000k

In this case system would search within music directory for files that have their names beginning with ‘Nirvana’ AND whose size is greater than 5000 Kilobytes.

(!) In fact AND operator is used by default, even if you don’t specify it (!)

15. find /music -size +5000k ! -name 'Nirvana*'

Here the command searches in music directory only for files that are greater than 5MB, but they should NOT have ‘Nirvana’ as the starting of their filenames.

16. find /music -name 'Nirvana*' -or -size +5000k

The system would search within music directory for files that have their names beginning with ‘Nirvana’ OR  all the files that are greater than 5000 Kilobytes.

Of course, there are much more things to say about find command, but the above mentioned examples will help you become more familiar with it in order to understand how powerful it is. Here you can check more parameters for find command.

Command Line – locate

As you probably remember given command is significantly faster than the previous one. In addition to that is much simpler. However you may encounter an error while running this command for the first time.  The problem is that Linux requires a database of all the files, so you need to update your database.

Here are some of the examples that will help you get familiar with locate command.

1. locate form.html

The system would produce a list of the locations where you could find files that are named as ‘form.html’. The result may look like that:

/usr/documents/site/form.html

2. locate '*.jpg' -q

The –q option is used to suppress any error messages, such as permission to access files and etc.

3. locate '*.pdf' -n 10

The system would limit the number of returned results to 10.

4. locate Polly.mp3 -i

The system would perform a case insensitive search, i.e. the case of the filenames wouldn’t be considered.

5. locate form.html -l 0

-l: means security level. “0″ turns security checks off. This will make search faster. “1″ turns security checks  on.

Such a command would make your search faster. If you replace –l 0 with –l 1, the process would take more time but the result will be more secure. Moreover it should be mentioned that –l 1 is the default action, if you don’t specify something else.

These were the most commonly used parameters.

Command Line – whereis

Due to the fact that we already know what this command is use for, we are going to go ahead with the parameters for the whereis command. Here they are:

-b – Search only for binaries.

-m – Search only for manual sections.
-s – Search only for sources.

-u – Search for unusual entries. A file is said to be unusual if it does not have one entry of each requested type. Thus `whereis -m -u *’ asks for those files in the current directory which have no documentation.

-B – Change or otherwise limit the places where whereis searches for binaries.

-M – Change or otherwise limit the places where whereis searches for manual sections.

-S – Change or otherwise limit the places where whereis searches for sources.

-f – Terminate the last directory list and signals the start of file names, and must be used when any of the -B, -M, or -S options are used.

1. whereis songbird

The system locates the directories where Songbird is stored

2. whereis -u -M /usr/man/man1 -S /usr/src -f *

In this case the system would search for any manual for any file in the current directory.

Command Line – which

No doubt the which command is the simplest one. There are no parameters to mention, so the only thing we would should do is to take a look at the following example:

which perl

The system would locate the executable location of the perl command. You get:

/usr/bin/perl

What to choose?

As you can see using command line to locate files is not as hard as it seemed to be. At the same time it’s significantly more powerful than the standard search options (graphical ones). Of course, if you are the one who is afraid of command line and don’t want to learn some really “cool stuff”, you can just add this post to your bookmarks and wait till “your time” comes. But in case you have an endless amount of files on your PC and from time to time need to find some of them really quickly, you probably know what to choose, don’t you?

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3. Linux Live

So why have I mentioned that? Just to emphasize that buying a netbook with Linux is not an easy task as it may seem to be. However there is quite a decent amount of machines to choose from.

Before we start reviewing the specs I would like you to pay attention to the fact that all the netbooks listed here have very comparable characteristics, i.e. it’s really up to you which one you are going to get.

Asus Eee PC 1000HD

This netbook is one of the largest models of the Eee series with a 10″ backlit LED display (1024×600 resolution).

It has 1.6 GHz Intel® Celeron M 353 Processor, 1 GB DDR2 RAM, 80 GB SATA hard drive, a 1.3-megapixel webcam, a 6 cell battery for 4.6 to 5.4 hours of battery life and the weight of 1.45kg.

This model easily functions in any connected environment with fast and complete connectivity (Wi-Fi 802.11 b/g) and can be connected to external devices via three USB 2.0 ports.

It has Bluetooth (optional), HD Audio, and a MMC/SD(SDHC) card slot, VGA output, Stereo speaker and Digital Array Mic.

In addition to that it goes with 10GB Eee Storage – ASUS provides 10 GB of online storage for the first 18 months after the purchase of this netbook.

There is a full range of applications to enhance communication and computing experiences.

Just for the Linux version there is a special Eee Connect feature for an easy way to connect two or more users through a remote desktop for easy troubleshooting.

For any additional info please visit the official web site.

Lenovo IdeaPad S10e

This model runs on SUSE Linux version.It goes with 1GB of DDR2 memory, almost netbook-standard 1.6GHz N270 Intel Atom processor, 160GB Hard Drive and Intel GMA 950 Graphics that easily handles your image processing needs whether you’re managing family photos or creating impressive presentations for work.

It’s pretty light and portable weighting 1.3kg and being 22-27.5mm thin.

The notable difference between the previously released S10 and the S10e is the inclusion of Lenovo’s “Quick Start” that represents a rebadged version of DeviceVM’s SplashTop, which is included on several Asus motherboards and its Eee Box desktop. SplashTop is a lightweight Linux distribution that can boot in a matter of seconds to give access to the web, music, photos, Skype or IM.

Thus as soon as you press the power button, it takes around 23 seconds for this netbook to get into a web browser. It has 802.11g Wi-Fi, so you’ll need a few more seconds to connect to an access point – altogether around 30 seconds for being able to start working.

In addition to that IdeaPad S10e has a recovery partition to return to the factory settings.

You can learn more here.

HP Mini 1000 Mi 10″

The HP Mini 1000 Mi is a compact and lightweight netbook. It has an Intel Atom N270 processor, 512 MB, 1GB or 2GB of RAM, an Intel GMA 950 graphics processor, integrated 10/100 BASE-T Ethernet LAN (RJ-45 connector), and Wireless-G card. In addition to that you can find HP mini webcam, built-in stereo speakers, a 2-in-1 integrated digital media reader, 2 USB Ports, and a 3 cell lithium polymer battery that lasts up to 3 hours.

There are two ways to store the data – flash based Solid State Drive (8 or 16 GB) or a 60 GB 4200RPM PATA hard drive. This model has a 10.1″ diagonal SD LED BrightView infinity widescreen display, and weighs only 1.02 kg.

It runs on HP’s Mobile internet (Mi) software which is a user-friendly interface built on Linux. There are a lot of applications installed, including a Web browser, Thunderbird for e-mail, Pidgin for instant messaging, OpenOffice.org, the HP MediaStyle music and movie player and etc. It should be mentioned that Linux shell is not directly linked from the Mi user interface – to access the Linux command line hit ALT+F2 and launch xterm.

HP offers free 24 x 7 service and support in the first year after the purchase.

Please check the official page for details.
Acer Aspire One 8.9″

This is a netbook made by Taiwanese electronics manufacturer Acer Incorporated. It has a 8.9″ CrystalBrite LED Backlit LCD screen with a resolution of 1024×600, a 1.6 GHz Intel Atom N270 processor, 512 KB L2 cache, Mobile Intel 82801 GBM chipset, 1 GB RAM, 8 GB of flash-based solid state storage, a 3-cell (or 6-cell) battery. The One is also available with a 2.5″ 120 GB hard disk drive.

The first release of this machine was in July 2008 and now it’s one of the most popular mini notebooks currently available, because of its comparably low price, a high-quality keyboard, a bright screen, the good build quality, and, admittedly, a lot nicer looking than most netbooks.

It has pre-installed Linpus Linux Lite version which is based on Fedora 8 offering, thus, a simplified user interface and features applications like the Mozilla Firefox Web browser and the free office package OpenOffice.org.

Acer provides a one year Warranty, upgradable to two years through Acer Advantage.

You can read more here.

Dell Inspirion Mini 9

This nice looking netbook is equipped with an Intel Atom Processor N270 1.6 GHz, 1 GB DDR2 at 533MHz, up to 32GB configured with a Solid State drive, an external portable CD/DVD-RW drive, 4-cell 32WHr Li-Ion Battery, a glossy 8.9 inch backlit LED display, an integrated 0.3M Pixel webcam, Intel Graphics Media Accelerator (GMA) 950, Integrated 10/100 LAN (RJ45), 3-in-1 Media Card Reader, 15-pin VGA video connector, Bluetooth®  Internal (2.0) mini-card, and 3 USB 2.0. As regards the OS it runs on Ubuntu Linux version 8.04.1.

Due to its ease of use Ubuntu is one of the most popular Linux distributions. This Ubuntu Version is optimized for the netbooks which have the restricted screen size. The pre-installed applications include the followings: Firefox Web browser, the E-mail client Thunderbird, Pidgin for instant messaging, the photo viewer F-Spot and the office suite OpenOffice.org.

To get more detailed specifications please visit the manufacturer’s web site.

Although all of them are very decent, I’m more than sure that you will choose the one that suits you the most.

Related posts:

1. Lenovo Linux Laptops
2. Ubuntu Notebook
3. EasyPeasy