When reading a file in C, which function can be used to check if the end of the file has been reached?
- fclose()
- feof()
- ferror()
- fseek()
The feof() function is used to check if the end of a file has been reached during file reading operations in C.
What is the primary purpose of the malloc function in C?
- To allocate memory for a single variable
- To allocate memory for an array of elements and initialize them
- To free memory allocated by calloc
- To reallocate memory for an array
The primary purpose of the malloc function in C is to allocate memory for a single variable. It returns a pointer to the allocated memory, which can be used to store data.
The function ________ is used to find the first occurrence of a character in a string in C.
- findchar
- locatechar
- strchr
- searchchar
The correct answer is strchr. strchr is a standard C function used to find the first occurrence of a character in a string. The other options are not valid C functions for this purpose.
When using dynamic memory allocation for arrays, which standard library function is used to release the memory that was previously reserved?
- calloc
- free
- malloc
- realloc
The correct function to release dynamically allocated memory is free. It is used to deallocate the memory previously reserved using malloc or calloc.
Which function is used to close a file that has been opened for reading or writing?
- closefile()
- endfile()
- fclose()
- stopfile()
In C, the fclose() function is used to close a file that has been opened for reading or writing. It is essential to close files to release system resources and ensure that data is properly saved.
A function in C returns a value to the calling function using the ________ keyword.
- output
- result
- return
- value
In C, the "return" keyword is used to return a value to the calling function. It specifies the value that the function will return.
What is the role of the 'continue' statement in a loop?
- It exits the program.
- It restarts the loop from the beginning.
- It skips the current iteration and continues with the next.
- It terminates the loop.
The 'continue' statement is used in loops to skip the current iteration and move to the next iteration. It does not terminate the loop but helps to skip certain iterations.
What is a pointer in C programming?
- A control structure in C
- A data type used for characters
- A function that returns values
- A variable that stores addresses
A pointer in C is a variable that stores the memory address of another variable. It's often used for dynamic memory allocation and accessing data indirectly.
How can a structure be passed to a function in C?
- By creating a copy inside the function
- By reference
- By using global variables
- By value
A structure can be passed to a function in C by reference (using a pointer or passing the address of the structure). This allows the function to modify the original structure's contents.
What is the significance of using pointers when working with structures in C?
- Pointers allow dynamic memory allocation.
- Pointers enable structures to be passed to functions efficiently.
- Pointers prevent data corruption in structures.
- Pointers simplify access to structure members.
Using pointers when working with structures in C is essential because they enable efficient access to structure members when they are passed to functions. This allows you to manipulate data inside structures without having to create copies of the entire structure.
When you increment a pointer in C, it advances the pointer by the size of the type to which it points, which is known as ________.
- Looping
- Memory allocation
- Pointer arithmetic
- Typecasting
When you increment a pointer in C, it advances the pointer by the size of the type to which it points, and this operation is known as pointer arithmetic. It allows you to navigate through data structures in memory.
When declaring a pointer in C, which symbol is used to denote that a variable is a pointer?
- #
- $
- &
- *
In C, the asterisk (*) symbol is used to declare a pointer variable. For example, int *ptr declares a pointer to an integer.