How does free know how much to free?

Question

In C programming, you can pass any kind of pointer you like as an argument to free, how does it know the size of the allocated memory to free? Whenever I pass a pointer to s

Answer 1

to answer the second question, yes you could (kind of) use the same technique as malloc() by simply assigning the first cell inside every array to the size of the array. that lets you send the array without sending an additional size argument.