How does a double pointer differ from a single pointer?
- Can store multiple values
- Points to a memory address
- Points to another pointer
- Stores double the data
A double pointer in C points to the memory address of a pointer, while a single pointer points to a single memory address. It allows for indirection, which can be useful in certain scenarios.
How does the strtok() function work in C?
- It calculates the length of a string
- It converts a string to uppercase
- It performs a binary search
- It splits a string into multiple substrings based on a delimiter
The strtok() function in C is used to split a string into multiple substrings based on a specified delimiter. It maintains state between calls, making it useful for tokenizing strings.
What function can be used to find the current position of the file pointer in a file?
- fseek()
- readPosition()
- getCurrentPointer()
- filePosition()
The correct function to find the current position of the file pointer in a file is 'fseek()'. It allows you to set the file position indicator to a specific location in the file and returns the current position. The other options are not valid functions for this purpose.
You are developing a program to manage the seating arrangement in a movie theater with rows and columns. How would you represent the seats using arrays?
- 1D Array
- 2D Array
- Linked List
- Queue (FIFO)
Seats in a theater can be efficiently represented using a 2D array, with rows and columns, making it easy to access and manage each seat's status.
How does the 'return' statement affect the flow of control within a loop?
- The 'return' statement exits the loop, returning control to the calling function or method.
- The 'return' statement has no impact on the flow of control within a loop.
- The 'return' statement skips the next iteration of the loop.
- The 'return' statement terminates the entire program when used within a loop.
The 'return' statement is used to exit a function or method prematurely and return a value. When a 'return' statement is encountered within a loop, it immediately exits the loop and returns control to the calling function or method. This can be useful for ending a loop under certain conditions or returning a value from the loop.
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.
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.
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.
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.
The ________ function is used to write data to a file in C.
- fprintf
- fread
- fscanf
- fwrite
In C, the fwrite function is used to write data to a file. It allows you to write binary data to a file stream.