Answers.com > Wiki Answers > Categories > Technology > Computers > Computer Programming > What is a null macro what is the difference between a null pointer and a null macro?

What is a null macro what is the difference between a null pointer and a null macro?

In: Computer Programming, School Subjects, Educational Methods and Theories [Edit categories]

Answer:

NULL Macro is simply what is defined as 0 in a macro provided by the library

Null pointer is a pointer which has 0 or NULL value stored and points to nowhwere still it points to 0x00 i.e. the first memory location of the OS

Null pointer != Uninitialized pointer because an uninitialised pointer can point anywhere in the memory location ...but a NULL pointer surely points to no where(but still behind the scene we can say that it only points to 0x00). Never we can retrive a Null pointer location using th"&" operator..neither will malloc/calloc return NULL IF THERE IS SPACE IN THE MEMORY. NULL pointer is unique !!
nishantnitb@aol.com

First answer by ID1022620139. Last edit by Nishantnitb. Contributor trust: 3 [recommend contributor ]. Question popularity: 6 [recommend question].

[report abuse]

Can you answer these Computer Programming questions?

	Why machine language is called low level language?	Answer it!
	What are the objectives of system design?	Answer it!
	What is floating point in computing?	Answer it!
	What is interrupt in assembly language?	Answer it!
	What is vertical micro code?	Answer it!

Relevant answers:

What is Difference between null macro and null pointer?
I'll assume that you're asking your question for C type language programming. A NULL pointer is a pointer that's guarnteed to point to nothing. This may be 0 in a UNIX/Linux system or some other...
What is the difference between Uninitialized pointers and Null Pointers?
Unitialized pointer may contain any value, so if you should use them, the results are unpredictable; NULL value on the other hands explicitly means that the pointer does not point anywhere. e.g.:...
What is the difference between void pointers and null pointers?
A void pointer is a pointer that has no type information attached to it. A null pointer is a pointer that points to "nothing". A null pointer can be of any type (void included, of course).
What is the difference between 0 and null?
Nothing - 0, Zero and null are the same things
What is the difference between void pointer 0 and NULL.?
If by 'void pointer 0' you mean '(void *)0', then it is equal to NULL.