DEFINITION OF POINTERS:
- Pointer,as the name indicates that it points to something that something is that we discuss now.Pointer is nothing but a variable which has the address of another variable.
- Pointers are largely used in C language and they make our program very simple and easily understandable
- Pointers and arrays are very closely linked to each other and in pointers we mostly use goto statement
- Let us assume that c is a character type and p is a pointer which points to c this situation we can implement in the program by an operator & which tells the address of a particular object so in our example we can write as (p=&c;).Which tells that address of c will be assigned to p.
- Rather than operator & we can also use * for the pointers let us see how these two are implemented from following program
int x = 0, y = 1, z[5];
int *ip; /* ip is a pointer to int */
ip = &x; /* ip now points to x */
ip = &x; /* ip now points to x */
y = *ip; /* y is now 0 */
*ip = 1; /* x is now 1
*/
ip = &z[0]; /* ip now points to z[0] */
now have you understood what is the difference between the two if not read below points
- int *ip says that *ip is an integer type and ip=&x says that ip assigns the value of x which is 0
- Then y=*ip means that the value of ip will be pointed that is 0 so value of y will become 0
- *ip=1 means the value of *ip is x and its value becomes as 1 and at last ip points to z[0]
The relationship between pointers and arrays are very strong in c language.This is explained in the following
- In an array we have declared a[10] means which has a blocks of size upto 10 and if we use pointers to the arrays we can point a particular array of size 10 example:if we have declared as int a[10] means it provides size 10 and let us consider p is a pointer first position in the array we declare it as int *p; p=a[0];
- In the above example p is a pointer which points to array location 0 which means it contains the address of a[0];
