C Programming - Pointers - Discussion

@Ramchandra

Can we write the above code with the help of "." operator ?

@sidesh:

In the above code instead of writing t->val=20;,

we can write
(*t).value=20; thats it..

. operator use when we have to acces stru member with array.

-> when we have to acces with pointer.

Can anybody say what is the actual difference, when we acces the member of struct by using "." operator & "->" operator ?

For structure...we have to point to the struct variables's data member..that why..-> is used....in structure for pointer representation.

Thanks kisan.

Pichuka says thanks to kissan.

There are two ways of accessing a structure member through a structure variable.
Ex:- struct student
{
int a;
float b;
}s1;

Here, S1 is a structure variable and a,b are the members.
**IF S1 IS A NORMAL STRUCTURE VARIABLE ,THEN IT CAN DIRECTLY ACCESS THE MEMBERS OF STRUCTURE!! THIS PROCESS IS CALLED DIRECT ACCESSING!!
FOR THIS PURPOSE WE USE '.'(DOT) OPERATOR.
EXAMPLE::- S1.A,S1.B ETC.
** BUT IF THE STRUCTURE VARIABLE S1 IS OF POINTER TYPE!!
i.e *S1,
THEN THIS STORES THE ADDRESS OF THE VARIABLE AND HENCE CANNOT BE DIRECTLY ACCESSED!! IT NEEDS TO BE ACCESSED INDIRECTLY THROUGH THE ADDRESS PRESENT WITH IT. THIS IS CALLED INDIRECT ACCESSING!!
FOR THIS PURPOSE WE USE '->'(ARROW) OPERATOR.
EXAMPLE ::- S1->A,S1->B etc.


FINALLY CONCLUSION:::-
IF STRUCTURE VARIABLE IS NORMAL, THEN WE USE '.'(DOT OPERATOR) ALSO CALLED AS DIRECT ACCESS OPERATOR.
SIMILARLY IF VARIABLE IS POINTER TYPE, THEN WE USE '->'(ARROW OPERATOR) ALSO CALLED AS INDIRECT ACCESS OPERATOR!!!

Thanks kisan

Finaly to normal structure variable we can use "."operator and to pointer type variable we can use "->"Operator.