What is the main difference between function declaration and function definition in C?
- Declarations contain the function's code
- Declarations specify the function's name
- Definitions declare the function's return type
- Definitions provide the function's implementation
The main difference between function declaration and function definition in C is that declarations specify the function's name and data types, while definitions provide the actual implementation of the function.
What does the strlen function from the C standard library do?
- Allocates memory for a new string
- Calculates the length of a string
- Compares two strings
- Copies one string to another
The strlen function in C calculates the length of a string by counting the number of characters until it reaches a null-terminator. It does not allocate memory or perform string copying.
What is the purpose of the 'sizeof' operator in C?
- It returns the address of a variable.
- It returns the size of a variable in bytes.
- It returns the type of a variable.
- It returns the value of a variable.
The 'sizeof' operator in C is used to determine the size (in bytes) of a variable or a data type. It is often used to allocate memory or work with data structures.
When designing a data packet structure for network communication, using ________ can help to minimize the packet size.
- Compression
- Encapsulation
- Fragmentation
- Segmentation
Encapsulation is a technique used to bundle data and functions into a single unit. It can help minimize the packet size by encapsulating data in a structured format for transmission over the network.
When dealing with an array of structures in C, what does each element of the array represent?
- A character array
- A floating-point number
- A function pointer
- A single structure instance
Each element of the array represents a single instance of the structure.
Which preprocessor directive would be used to conditionally compile certain blocks of code?
- #define directive
- #ifdef directive
- #include directive
- #pragma directive
The #ifdef directive is used to conditionally compile code based on whether a certain macro has been defined. It allows you to include or exclude specific code blocks based on preprocessor macros.
What is the function of the #define preprocessor directive in a C program?
- Controls the execution flow of the program
- Declares a variable within the program
- Defines a constant value for use in the program
- Includes a header file in the program
The #define directive is used to define constants. It allows you to specify a constant value that is used throughout the program, making it easier to maintain and modify the code.
What happens when realloc is called with a size parameter of zero?
- It frees the previously allocated memory.
- It leads to a memory leak.
- It reallocates the memory with a size of zero.
- It returns a null pointer.
When realloc is called with a size parameter of zero, it frees the previously allocated memory and returns a pointer to the freed memory, effectively deallocating it.
Which statement is true regarding the difference between inline functions and macros in C?
- Inline functions can have local variables
- Inline functions cannot be used with conditional compilation
- Macros are preprocessed
- Macros are type-safe
Macros in C are preprocessed, meaning they are replaced by their definitions before compilation. This can lead to unexpected behavior and debugging challenges. In contrast, inline functions are compiled as proper functions with type safety and can have local variables.
An array of structures can be used to represent a collection of ________ that share the same attributes but have different values.
- Constants
- Functions
- Objects
- Variables
Arrays of structures in C are commonly used to represent a collection of objects (or variables) that share the same attributes but have different values, making them an efficient way to manage related data.