What is indirection? Ans. If you declare a variable, its name is a direct reference to its value. If you have a pointer to a variable, or any other object in memory, you have an indirect reference to its value. If p is a pointer, the value of p is the address of the object. *p means 'apply the indirection operator to p'; its value is the value of the object that p points to. (Some people would read it as 'Go indirect on p.') *p is an lvalue; like a variable, it can go on the left side of an assignment operator, to change the value. If p is a pointer to a constant, *p is not a modifiable lvalue; it can't go on the left side of an assignment. Consider the following program. It shows that when p points to i, *p can appear wherever i can. #include int main() { int i; int *p; i = 5; p = & i; /* now *p == i */ printf('i=%d, p=%P, *p=%d\n', i, p, *p); *p = 6; /* same as i = 6 */ printf('i=%d, p=%P, *p=%d\n', i, p, *p); return 0; } After p points to i (p = &i), you can print i or *p and get the same thing. You can even assign to *p, and the result is the same as if you had assigned to i.

Download the Study24x7 App, so you can connect and collaborate.