In C pointer terminology, what does the expression (void*)0 represent?

Introduction / Context:
Null pointers are used to indicate that a pointer intentionally does not point to any valid object or function. C defines specific ways to write a null pointer constant so that it can be converted to any pointer type safely.

Given Data / Assumptions:

• We are evaluating the literal (void*)0.
• Standard C semantics for pointer constants apply.

Concept / Approach:
(void*)0 is a canonical spelling of a null pointer constant: the integer constant 0 explicitly cast to pointer-to-void. When assigned to or compared with any object pointer type, it becomes that type’s null pointer. It does not represent a generic “void pointer value” in use; it specifically denotes the absence of a valid address.

Step-by-Step Solution:
Start with the integer constant 0, which is a null pointer constant in C.Cast to (void*) to make the null-ness explicit and type-safe for function overloading or diagnostics.Use in code: int p = (void)0; /* p becomes a null pointer /

Verification / Alternative check:
Comparisons like if (p == NULL) or if (p == (void)0) are equivalent when p is a pointer to object.

Why Other Options Are Wrong:

• “Representation of void pointer” is vague; (void*)0 is not a generic pointer value, it is the null pointer value of type void*.
• “Error” and “None of above” are incorrect because the expression is well-defined and standard.

Common Pitfalls:
Confusing (void*)0 with 0 or NULL in C++ where nullptr is preferred; assuming null pointers are all-bits-zero at the machine level (the standard does not require that).

Final Answer:
Representation of NULL pointer.