What is the significance of the size_t return type in the fwrite function?
- It determines the file's size.
- It indicates the file's creation date.
- It is used to specify the file mode.
- It represents the number of items written to the file.
The size_t return type in the fwrite function signifies the number of items successfully written to the file. This is important for checking the success of the write operation.
You're working on a program that continuously monitors sensor data and reacts when a certain threshold is reached. Which loop construct would be most suitable for this task?
- do-while loop
- for loop
- if-else statement
- while loop
The most suitable loop construct for continuously monitoring sensor data is a 'while loop.' A while loop checks a condition and executes its code block repeatedly as long as the condition is true. This allows continuous monitoring until the threshold is reached.
What is a potential risk of using the gets() function for reading strings in C?
- It always returns NULL
- It can lead to buffer overflow
- It doesn't exist in C
- It has a higher time complexity
The gets() function is risky because it does not perform bounds checking and can lead to buffer overflows, potentially exposing the program to security vulnerabilities.
In a program managing a database of students, each student has attributes like name, age, and grades. How would pointers to structures be beneficial in this scenario?
- Enhance database security
- Improve data organization
- Minimize CPU usage
- Streamline user input
Pointers to structures can be beneficial in this scenario by improving data organization. By using pointers to structures, you can efficiently manage and access student information, such as name, age, and grades, making the database more organized and accessible. This optimization helps in effective data management.
In a database application, you need to sort a list of names (strings) in alphabetical order. Which string handling function might be useful in this scenario?
- strchr
- strcmp
- strnlen
- strtok
To sort a list of names in alphabetical order, the strcmp function is useful. It compares two strings and returns a value indicating their relative order. strtok is used for tokenizing strings, strchr searches for a character in a string, and strnlen provides the length of a string up to a specified limit.
Which preprocessor directive is used to include a header file in a C program?
- #define
- #ifdef
- #ifndef
- #include
The preprocessor directive #include is used to include a header file in a C program. It allows you to use functions and declarations from the included file in your program.
What is the impact of using inline functions on the size of the compiled binary?
- Decreases binary size
- Depends on compiler optimization
- Increases binary size
- No impact on binary size
Inline Functions are a feature in C/C++ that help reduce function call overhead. They can lead to smaller binary sizes due to inlining, where the function's code is inserted directly at the call site, reducing the need for a separate function call.
In C, a function pointer can be used to call a function without knowing its ________ at compile time.
- Function name
- Memory location
- Parameters
- Return type
Function pointers in C allow you to call a function by its name dynamically, making it possible to call functions without knowing their names at compile time.
The function ______ is used in C to print a string to the standard output.
- print()
- puts()
- display()
- writeString()
The correct option is b) puts(). This function is used to print a string to the standard output, followed by a newline character.
An array of ________ can be used to call different functions based on an index.
- Functions
- Objects
- Pointers
- Structures
In C, you can use an array of function pointers to call different functions based on the index. Function pointers point to functions, making it possible to create arrays of functions and select them dynamically.
You are working on optimizing a simulation program that makes numerous calls to small functions. What technique can be used to potentially speed up the execution without significantly changing the logic of the program?
- Inlining small functions
- Converting the program to assembly code
- Increasing the stack size
- Using larger data types
Option A is the correct answer. Inlining small functions can potentially speed up the execution by reducing the overhead of function calls. It doesn't significantly change the logic of the program. Options B, C, and D are not the best approaches for optimizing the program.
How can a dangling pointer issue be avoided after freeing memory in C?
- Call free() twice
- Increase the pointer value after freeing
- Set the pointer to NULL after freeing
- Use a double pointer
To avoid a dangling pointer issue, it's a good practice to set the pointer to NULL after freeing the memory it points to. This way, the pointer won't accidentally be accessed, preventing potential issues.