C - What is a const pointer?

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What is a const pointer?

Total Answers and Comments: 4

Last Update: June 09, 2007

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Submitted by: Prasad

Constant pointer is NOT pointer to constant. Constant pointer means the pointer is constant. For eg:
Constant Pointer
int * const ptr2 indicates that ptr2 is a pointer which is constant. This means that ptr2 cannot be made to point to another integer. However the integer pointed by ptr2 can be changed.

Where as a Pointer to constant is
const int * ptr1 indicates that ptr1 is a pointer that points to a constant integer. The integer is constant and cannot be changed. However, the pointer ptr1 can be made to point to some other integer.

Above answer was rated as good by the following members:
selloorhari, bhavyam, tigersasi

October 04, 2005 12:07:46

mayank

RE: What is a const pointer?

There are cases when you need to define a constant pointer to a variable/object; for instance, when taking a function address, or when you want to protect a pointer from unintended modifications such as assignment of new address, pointer arithmetic, etc.

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April 27, 2007 04:30:24

Prasad

RE: What is a const pointer?

Constant pointer is NOT pointer to constant. Constant pointer means the pointer is constant. For eg:
Constant Pointer
int * const ptr2 indicates that ptr2 is a pointer which is constant. This means that ptr2 cannot be made to point to another integer. However the integer pointed by ptr2 can be changed.

Where as a Pointer to constant is
const int * ptr1 indicates that ptr1 is a pointer that points to a constant integer. The integer is constant and cannot be changed. However, the pointer ptr1 can be made to point to some other integer.

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June 08, 2007 19:34:48

neverd

Member Since: June 2007 Contribution: 11

RE: What is a const pointer?

A pointer that cannot be changed to point other memory or object, however the value it points to can be changed.

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June 09, 2007 05:04:39

pradeep kumar v.v.n.k

RE: What is a const pointer?

a const pointer means the pointer which represents the address of one value. so if you declare a pointer inside the function, it doesn't have scope outside the function. if it is also available to the outside function whenever we declare a pointer as const.

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