Q1: What is the correct syntax for declaring a pointer to an integer in C language?
Answer:
A pointer to an integer is declared by specifying the data type int followed by an asterisk * and the pointer’s name. The asterisk indicates that the variable is a pointer.
Q2: How is the memory address of a variable assigned to a pointer in C?
Answer:
The memory address of a variable is assigned to a pointer using the address-of operator &. This makes the pointer store the location in memory where the variable is kept.
Q3: How can a pointer be initialized in C, and what is the significance of NULL in pointer initialization?
Answer:
A pointer can be initialized either by giving it the address of a variable or by assigning it NULL. NULL means the pointer is not pointing to any valid memory location. Initializing with NULL is important to prevent errors when a pointer is used without a proper value.
Q4: In what scenarios is call by reference useful, and how is it simulated using pointers in C functions?
Answer:
Call by reference is useful when a function needs to modify the original value of a variable. In C, this is simulated by passing the memory address of the variable to the function. The function then uses the pointer to access and change the value directly in memory.