What does the `calloc()` function do?

The calloc() function is specifically designed to allocate memory for an array of elements and initializes all the allocated memory to zero. This capability distinguishes calloc() from other memory allocation functions that do not initialize the allocated memory.

When using calloc(), a programmer can specify the number of elements needed and the size of each element. The function then allocates enough memory for the total of these elements and sets each byte in the allocated memory block to zero. This is particularly useful in cases where a clean slate is needed, ensuring that any numerical types will start as zero, and pointers will be set to NULL.

This initialization can help prevent bugs that may arise from using uninitialized memory, which may contain garbage values left over from other processes. Thus, when choosing memory allocation functions in C, it’s important to consider whether initialization is required, and calloc() serves that purpose effectively.