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What is a null pointer?
There are times when it’s necessary to have a pointer that doesn’t point to anything. The macro NULL, defined in <stddef.h>, has a value that’s guaranteed to be different from any valid pointer. NULL is a literal zero, possibly cast to void* or char*. Some people, notably C++ programmers, prefer to use 0 rather than NULL.
 
The null pointer is used in three ways:
1) To stop indirection in a recursive data structure
2) As an error value
3) As a sentinel value
 


  
Total Answers and Comments: 1 Last Update: March 22, 2006   
  
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March 22, 2006 01:42:31   #1  
supriya ahire        

RE: What is a null pointer?

hi

Null pointer: When referring to computer memory a null pointer is a command used to direct a software program or operating system to an empty location in the computer memory. Commonly the null pointer is used to denote the end of a memory search or processing event. In computer programming a null pointer is a pointer that does not point to any object or function.

In the programming language c NULL is an available command that can be used.

Regards

Supriya Ahire.


 
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