Pointers in C programming

 Pointers in C...

     In this section contains example programs demonstrating            the use of pointers.

•  Pointers in C language is a variable that stores or points the address of another variables.
•  A Pointer in C is used to allocate memory dynamically mean  at run time. The pointer variable might be belong to any of the datatype i.e. int, float, char, double, short etc.

        Syntax : data_type *var_name; Example : int *p;  char *p;
         here, * is used to denoted that “p” is pointer variable and not a normal variableNormal variable            stores the value whereas pointer variable stores the address of the variables.

• In c  The content of the C pointer always be a whole number i.e. address.

1.   Always C pointer is initialized to null mean zero, i.e. int *p = null.
2.   value of null pointer is 0.
3.   & symbol is used to get the address of the variable.
4.   * symbol is used to get the value of the variable that the pointer is pointing to.
5.    If a pointer in C is assigned to NULL, it means it is pointing to nothing.
6.    Two pointers can be subtracted to know how many elements are available beetween these          two pointers.
7.    Pointer addition, multiplication, division are not allowed.
8.    size of any pointer is 2 byte (for 16 bit compiler).

            #include <stdio.h>
               int main()
                 {
               int *ptr, q;
                     q = 30;
                /* address of q is assigned to ptr */
                 ptr = &q;
              /* display q's value using ptr variable */
           printf("%d", *ptr);
               return 0;

        OUTPUT:

             30