In the context of function pointers in C, a callback function is a function that is passed as a(n) ________ to another function.
- Argument
- Parameter
- Pointer
- Variable
In C, a callback function is passed as a parameter to another function, allowing the function to call back to the provided function.
What happens if you try to modify a character in a string literal?
- It converts the string to uppercase
- It is allowed and won't cause any issues
- It raises a compile-time error
- It raises a run-time error
Modifying a character in a string literal is not allowed because string literals are stored in read-only memory, and attempting to modify them will result in a compile-time error.
What is the purpose of command line arguments in a C program?
- To display error messages
- To enhance program security
- To format program output
- To provide input data to the program
Command line arguments are used to provide input data to a C program. They allow users to pass values to the program when it's executed, making it versatile and interactive.
In C, the ________ operator is used to find the remainder of a division operation.
- Modulus (%)
- Division (/)
- Exponentiation (^)
- Multiplication (*)
The correct option is (a) Modulus (%). The modulus operator (%) in C is used to find the remainder of a division operation. For example, 10 % 3 equals 1 because the remainder when 10 is divided by 3 is 1.
You are tasked with optimizing memory usage in a real-time application that processes complex data structures. How can pointers assist in achieving this goal?
- Efficiently handle data references
- Implement data compression
- Minimize CPU load
- Reduce data complexity
Pointers can assist in optimizing memory usage by efficiently handling data references. They allow the application to store references to complex data structures rather than duplicating the data itself. This reduces memory consumption and benefits the real-time application's performance by avoiding unnecessary data duplication.
In C, the first element of an array can be accessed using index ________.
- -1
- 0
- 1
- 10
In C, arrays are zero-indexed, so the first element can be accessed using index 0.
What would be an appropriate use case for a union in C?
- Defining a new data type
- Ensuring data integrity
- Implementing complex data structures
- Storing multiple values of different types simultaneously
Unions are often used when you need to store multiple values of different types in the same memory location. Only one of the union's members can hold a value at a given time.
In C, what is the main advantage of using bit fields in a structure?
- Allowing dynamic memory allocation
- Enabling the use of multi-threading
- Reducing the memory footprint
- Simplifying file I/O
Bit fields in C structures allow you to efficiently use memory by storing data in a compact format. This is useful for optimizing memory usage when dealing with data that has a fixed range of values.
The function ________ in C changes the size of the memory block pointed to by a given pointer.
- realloc()
- free()
- malloc()
- calloc()
The correct option is 'realloc()'. The realloc() function is used to change the size of a previously allocated memory block, making it suitable for resizing dynamic arrays.
You're writing a program that needs to efficiently calculate the power of 2 for a given exponent. Which operator would be most efficient to use?
- * (Multiplication)
- ** (Exponentiation)
- << (Left Shift)
- ^ (Bitwise XOR)
The correct answer is C) ** (Exponentiation). To efficiently calculate the power of 2 for a given exponent, you should use the exponentiation operator (**).