What's the point of malloc(0)?

Question

I just saw this code:

artist = (char *) malloc(0);

...and I was wondering why would one do this?

Answer 1

There are a lot of half true answers around here, so here are the hard facts. The man-page for malloc() says:

If size is 0, then malloc() returns either NULL, or a unique pointer value that can later be successfully passed to free().

That means, there is absolutely no guarantee that the result of malloc(0) is either unique or not NULL. The only guarantee is provided by the definition of free(), again, here is what the man-page says:

If ptr is NULL, no operation is performed.

So, whatever malloc(0) returns, it can safely be passed to free(). But so can a NULL pointer.

Consequently, writing artist = malloc(0); is in no way better than writing artist = NULL;