Pointers in C Quiz

Pointers in C

• A pointer in C contains the memory address of a variable.
• It enables dynamic memory allocation and manipulation of variable addresses directly.
• Pointers can point to any data type, including arrays and functions.

Size of a Pointer

• The size of a pointer in C is typically 4 bytes on a 32-bit system and 8 bytes on a 64-bit system.
• Size may vary depending on the architecture and data type it points to.

Dereferencing Invalid Pointers

• Dereferencing a pointer without a valid memory address results in undefined behavior.
• This can lead to segmentation faults or access violations.

Call by Value

• In call by value, the actual parameter’s value is copied into the function's formal parameter.
• Changes made to the formal parameter do not affect the actual parameter outside the function.

Call by Value vs. Call by Reference

• Call by value passes a copy of a variable, while call by reference passes a reference (or address) to the actual variable.
• Changes to formal parameters in call by reference affect the actual parameters, allowing for direct manipulation of the original data.

Role of Formal Parameters

• Formal parameters act as placeholders in function definitions that receive values of actual parameters during function calls.
• They define the types of inputs that a function can accept.

Value Inside Function (Call by Value)

• Inside a function that uses call by value, the value of the formal parameter is local and separate from the actual parameter.
• Modifications to the formal parameter do not alter the actual parameter outside the function.

Example Function 'Square'

• The example function 'square' takes an integer input and returns its square.
• It showcases the use of call by value, where the original variable remains unchanged after the function call.

Test your knowledge of pointers in C with this quiz. Explore what a pointer in C contains, its size, and the consequences of dereferencing a pointer without a valid memory address.