How to do calculations on Command Prompt ?

The command processor CMD.EXE comes with a mini-calculator that can perform simple arithmetic on 32-bit signed integers:
C:\>set /a 2+2
4
C:\>set /a 2*(9/2)
8
C:\>set /a (2*9)/2
9
C:\>set /a “31>>2″
7
Note that we had to quote the shift operator since it would otherwise be misinterpreted as a “redirect stdout and append” operator.
For more information, type set /? at the command prompt

Enjoy Friends........

Free Download Videos from Other Websites and YouTube Without Software Download

Hello Friends,we all know about YouTube , It is video Sharing Websie.From here Users can upload,watch and share new video.You can find all videos on YouTube and if you like any video then you want to download it then you can find many ways on other websites but from there you have to download some softwares or you have to convert this videos to another format.So it is very difficult to download to download .
But if you download videos easily from YouTube then i know one way by which you can download videos easily in .flv format.

Click Here to download video from youtube and other websites

10 tips for new Mac users,Switching from Windows...

Being the sort of guy who likes to use keyboard shortcuts rather than having to reach for the mouse all the time, I felt a bit hostile once I got my new Macbook Pro. I knew how to do task X or Y on Windows with a few keystrokes, but having moved to Mac OS X (read 10 not X, as I made the mistake!), I found myself feeling annoyed that I didn't know my way around the OS smoothly.
So I searched the Internet to find out about some of the more obscure shortcuts. Below I've listed and explained some shortcuts that a new Mac user, especially those coming from a Windows environment, may not be aware of. It's definitely made my life easier, hopefully you're a new mac user, these will be of use.
1. Forward Delete On a Windows computer, the Backspace key deletes from right to left, where as the Delete key is used to delete from left to right (i.e. forward delete). But on a mac, there is no delete key (at least not the MBP). So at first I found myself clicking everywhere on emails to delete! So the solution: Fn+Delete. Simple!
2. Expose with F9 I found it annoying that I had to click Fn+F9 to bring Expose up. If I clicked F9, it would change the keyboard light intensity. So, the hardware F9 and the sofware F9 have to be swapped. This is how: Go to System Preferences > Keyboard and Mouse, click the Keyboard tab and check the box that says "Use the F1-F12 keys to control software features". Now when you press F9, it will bring Expose and when you press Fn+F9 it will change the keyboard light intensity. This is the same for the other keys like volume and display brightness. For example, the volume increase is situated on F5, which is used as the refresh button in browsers in Windows. By ticking the box mentioned above, you can use F5 to refresh you browser now!
3. Right Click Windows users love their right click button! It just doesn't make sense to have a computer without it! Well... Macs don't! They have what is called a contextual menu, and it is evoked by control clicking. Now there's two things you can do: First one works in Firefox (I couldn't get it to work in other programs or in Finder). All you do is click and hold and very soon the contextual menu appeares. You can do that anywhere: links, tabs, bookmarks, etc. Other method, which works everywhere is done as follows. First, go to System Preference > Keyboard and Mouse. Go to the Trackpad tab (assuming MBP) and click the "Tap trackpad using two fingers for secondary click". Now if you two-finger-click on the trackpad, the right click menu appears! So convenient, specially when combined with two finger scrolling.
4. Tab key Again, whenever I faced a dialog box with buttons, I used the tab key to navigate between the buttons. On a webpage, this was also true. On a mac, you'll probably get confused, as the tab key doesn't do that! Again, head over to System Preferences > Keyboard and Mouse, then go to the Keyboard Shortcuts tab and click the radio button at the end saying "All controls". Now you can use tab to move around just like windows! Still one thing left... say you have the shutdown dialog box and you use the tab key to navigate to Sleep, if you press Enter, it will shutdown, even though the blue highlight is around the Sleep button. You have to press the Spacebar instead! Confusing at first!
5. Shutdown shortcut Speaking of the shutdown dialog, you can bring it up using Control+eject. In Windows I used Win Key+U, then U again.
6. Maximise button and what it does So you press the green maximise button, but it doesn't maximise? Well, the button only maximises as much is neccessary. So, say you are reading a PDF document. If you zoom in on your document and then press maximise, you will see that the window will become large enough to hold the whole document. And if you zoom out and press the green button again, it will shrink to fit it. Again, different to Windows and needs some getting used to!
7. Alternative to minmise We saw what the maximise button does, what about the minimise button? Well, it "sucks" (as I like to call it) the document to the dock. What is the point of minimising? To clear your screen, to get rid of clutter. So, you can try these two alternatives depending on the need. Either press F11 to see the desktop, or press Command+H to hide the current window, which is what I tend to do.
8. Moving menu bar icons In Windows you can't move the task bar icons (or I don't know how), but on Mac, you can Command click them and move them around. Neat!
9. No Ctrl+Al+Delete ? I always clicked that well known combination to see my RAM and network usage and see what applications are running. On the Mac, go to Applications > Utilities > Activity Monitor. Also, you can click Option+Command+Esc to bring up the Force Quit menu, if you need to quit any application that is not responding.
10. Cool shortcut combo To finish off, I'l give a cool (relatively) shortcut combination. Clicking Control+Option+Command+8 will turn the screen in some sort of high contrast mode, but more like an X-ray screen! Try it, it's fun! Hopefully, at least there has been one tip that has been useful to you. Please share other tips and tricks that you know in the comments. It is always interesting to learn new things.

Update: This article has been translated into Japanese at netafull.net. Visit here to read it.


Enjoy Friends For Mac OS Users

Top Ten Mac OS X Tips for Unix Geeks

Enjoy Friends ....... U Use This.....

It's been a few years since the release of the book I co-wrote with Ernie Rothman, Mac OS X for Unix Geeks, and I see that a few things have changed since I originally offered the top 10 tips that I gathered while working on the book. These tips will show you the differences between Mac OS X and other flavors of Unix; help you find the bits that resemble the Unix you are used to; and even feather your nest with ports of popular open source applications.

1. Where's My Shell?

A Unix geek won't get too far without a shell, right? You can find the Terminal application by navigating to /Applications/Utilities in the Finder. Drag the Terminal application to your dock so you can access it quickly.
When you start up the Terminal, you'll be greeted with the default user shell, tcshbash. You can customize the Terminal's appearance and settings by selecting Window Settings from the Terminal menu. You can set the startup shell by selecting Preferences from the Terminal menu.

2. Sudo, Not Su

By default, the root user is disabled on Mac OS X. If you need to do something as root, use the sudo command. To use this command, pass in the command and arguments you want to execute, as in: sudo vi /etc/hostconfig. You'll need to be a user with Administrative privileges. The main user has this capability by default.
If you need a root shell, you can always use sudo tcsh or sudo bash. If you want to enable the root user, it's as simple as giving root a password with sudo passwd root. You'll also want to open System Preferences, choose Accounts, then Login Options and change Display Login Windows as: to Name and password. Then you can log out and log in as the root user.

To get compilers and many other development tools, you'll need the Mac OS X Developer Tools. If you bought the boxed version of Mac OS X, the Developer Tools should be included on a separate CD-ROM. If you bought a new Macintosh that came with Mac OS X preinstalled, the Developer Tools installer will probably be in /Applications/Installers. Failing either of those, or if you'd like to get the latest version of the tools, they are available to Apple Developer Connection (ADC) members.

3. Startup

Mac OS X startup is nothing like other Unix systems. Most significantly, Mac OS X has nothing like the /etc/init.d directory. Instead, it finds its startup items via /System/Library/StartupItems (for system startup items) or /Library/StartupItems the launchd startup program. You can read all about it in this ADC article.

4. Filesystem Layout

If you open up a Finder window to the top-level of your hard drive, you'll see that familiar friends like /var and /usr are missing. They are actually hidden (more on that later). If you open up a Terminal shell and do an ls /, you'll see the missing folders, as well as a few others, such as /Library and /Developer.
The following table lists some of these folders that you'll see (Appendix A of Mac OS X for Unix Geeks contains a more comprehensive list):

File or Directory	Description
.DS_Store	This file contains Finder settings.
.Spotlight-V100	This file contains Spotlight settings.
.Trashes	This directory contains files that have been dragged to the Trash.
.fseventsd	Used by the File System events framework.
.hotfiles.btree	This is used by Mac OS X's Hot-File-Adaptive-Clustering feature to keep track of frequently used files.
.vol/	This directory maps HFS+ file IDs to files.
Applications/	This directory holds all your Mac OS X applications. Check out its Utilities/ subdirectory for lots of fun stuff!
Desktop DB, Desktop DF	The Classic Mac OS desktop database.
Desktop Folder/	The Mac OS 9 desktop folder.
Developer/	Apple's Developer Tools and documentation. Only available if you have installed the Developer Tools.
Library/	Support files for locally installed applications, among other things.
Network/	Network-mounted Application, Library, and Users directories, as well as a Servers directory.
Shared Items/	Use by Mac OS 9 to share items between users.
System Folder/	The Mac OS 9 System Folder.
System/	Contains support files for the system and system applications, among other things.
Temporary Items/	Temporary files used by Mac OS 9.
TheVolumeSettingsFolder/	This directory keeps track of details such as open windows and desktop printers.
Trash/	Mac OS 9 trash folder.
Users/	Home directories.
VM Storage	Mac OS 9 virtual memory file.
Volumes/	Contains all mounted filesystems.
automount/	This directory handles static NFS mounts.
bin/	Contains essential system binaries.
cores/	If core dumps are enabled (with tcsh's limit and bash/sh's ulimit commands), they will be created in this directory as core.pid.
dev/	This directory contains files that represent various devices.
etc/	This directory contains system configuration files.
mach	This is a symbolic link to the /mach.sym file.
mach.sym	Kernel symbols.
mach_kernel	The Darwin kernel.
private/	Contains the tmp, var, etc, and cores directories.
sbin/	Executables for system administration and configuration.
tmp/	Temporary files.
usr/	This directory contains BSD Unix applications and support files.
var/	This directory contains frequently modified files such as log files.

5. Different Kinds of Hidden Files As with other Unix flavors, you can make a file invisible by prefixing its name with a ., as in /.vol. This has the effect of making it invisible in the Finder, as well as when you issue an ls without the -a option. Mac OS X also uses a file in the root directory (.hidden) to maintain a list of files that should be hidden from the Finder. Also, HFS+ (the filesystem used by Mac OS) files and directories can have a hidden attribute set using the SetFile command, as in SetFile -a V SomeFile. (The SetFile command is available in /Developer/Tools after you install the Mac OS X Developer Tools package described in the sidebar.) This setting won't take effect until you relaunch the Finder. You can log out and log in again or use the Force Quit option from the Apple menu. You can turn off the invisible bit with SetFile -a v SomeFile. See the manpage for SetFile for more details. (Note that invisible files are only invisible from the Finder; you can still see them with ls.) 6. Aliases and Links There are two ways to create links to files. The first is to select the file in the Finder, and drag it to a new location while holding down the Option and Command keys (or select Make Alias from the File menu). This creates a Mac OS alias that Cocoa, Carbon, and Classic applications can follow. However, Unix applications will ignore those links, seeing them as zero-byte files. You can also create a link with ln or ln -s. If you use this kind of link, Unix, Cocoa, Carbon, and Classic applications will happily follow it. 7. X11 Mac OS X does not come with the X Window System. For native applications, it uses an advanced graphics system called Aqua. But if you want to run X11 applications, you're in luck: Apple has its own X11 implementation with nice Aqua integration, and there is an installer for it on your Mac OS X installation CD-ROM or DVD. If it wasn't installed by default, run the Optional Installs package on your install disc. You'll be able to run X11 applications side-by-side with Mac OS X applications, and they'll look great. 8. Fink Are there some Unix or Linux applications that you're missing? Check out the Fink project, which modifies open source applications so they'll compile and run on Mac OS X. Fink already includes an impressive array of applications, and more are on the way. Related Reading Mac OS X for Unix Geeks By Brian Jepson, Ernest E. Rothman + 9. /etc is Not Always in Charge If you've come to Mac OS X from another Unix, you may expect that you can add users and groups to the /etc/passwd and /etc/group files. By default, Mac OS X only uses these file in single-user mode. If you want to add a user or group, it will need to go into the Directory Services database, a repository of local directory information. For more information, see this ADC article,Open Directory and the dscl Tool. 10. Shutdown Doesn't Really For a long time, Mac OS X couldn't execute custom actions at shutdown. The SystemStarter framework (which predates launchd) can perform custom shutdown actions when the system is shutting down. For more information, see "Start Me Up: Writing and Understanding OS X StartupItems" (the ADC launchd article mentions that services that need an explicit shutdown procedure will need the old SystemStarter framework).