Pointers এর ব্যবহার ও তার প্রয়োজনীতা

Chapter 11 - An Introduction to Pointers

You've learned about many important C data types, operators, functions, and loops in the last 10 hours. In this lesson you'll learn about one of the most important and powerful features in C: pointers. The topics covered in this chapter are

    Pointer variables
    Memory addresses
    The concept of indirection
    Declaring a pointer
    The address-of operator
    The dereference operator




Summary

In this lesson you've learned the following:

•     A pointer is a variable whose value is used to point to another variable.
•     A variable declared in C has two values: the left value and the right value.
•     The left value of a variable is the address; the right value is the content of the variable.
•     The address-of operator (&) can be used to obtain the left value (address) of a variable.
•     The asterisk (*) in a pointer declaration tells the compiler that the variable is a pointer variable.
•     The dereference operator (*) is a unary operator; as such, it requires only one operand.
•     The *ptr_name expression returns the value pointed to by the pointer variable ptr_name, where ptr_name can be any valid variable name in C.
•     If the right value of a pointer variable is 0, the pointer is a null pointer. A null pointer cannot point to valid data.
•     You can update the value of a variable referred by a pointer variable.
•     Several pointers can point to the same location of a variable in the memory.