Pointer

Pointer is a variable which holds the memory address of annother variable. Pointers are represented by '*'. It is derive data type in C. Pointer returns the value of stored address.

Syntax:

  

    < data_type > *pointer_name;
  

In above syntax,

* = variable pointer_name is a pointer variable.

pointer_name requires memory location

pointer_name points to a variable of type data type.

How to Use?

int *tot;

Illustration:

int tot = 95

Figure:

In above example, the statement instructs the system to find out a location for integer variable quantity and puts the values 95 in that memory location.

Features of pointer:

• Pointer variable should have prefix '*'
• Combination of data types is not allowed.
• Pointers are more effective and useful in handling arrays.
• It can also be used to return multiple values from a function using function argumennts.
• It supports dynamic memory management.
• It reduces complexity and length of a program.
• It helps to improve execution speed that results in reducing program execution time.

  

    #include< stdio.h >
    #include< conio.h >

    void main()
    {
      int a = 10;
      int *ptr;
      clrscr();
      ptr = &a;
      printf("\n\tValue of a : %d", a);
      scanf("\n\n\t Value of pointer ptr : %d", *ptr);
      printf("\n\n\t Address of pointer ptr : %d", ptr);
      getch();
    }

    output:

    Value of a : 10

    Value of pointer ptr : 10

    Address of pointer ptr : -12