What REALLY happens when you don't free after malloc?

Question

This has been something that has bothered me for ages now.

We are all taught in school (at least, I was) that you MUST free every pointer that is allocated. I\'m a

Answer 1

If you're using the memory you've allocated, then you're not doing anything wrong. It becomes a problem when you write functions (other than main) that allocate memory without freeing it, and without making it available to the rest of your program. Then your program continues running with that memory allocated to it, but no way of using it. Your program and other running programs are deprived of that memory.

Edit: It's not 100% accurate to say that other running programs are deprived of that memory. The operating system can always let them use it at the expense of swapping your program out to virtual memory (). The point is, though, that if your program frees memory that it isn't using then a virtual memory swap is less likely to be necessary.