0xDEADBEEF vs. NULL

Question

Throughout various code, I have seen memory allocation in debug builds with NULL...

memset(ptr,NULL,size);

Or with 0xDEA

Answer 1

http://en.wikipedia.org/wiki/Hexspeak

These "magic" numbers are are a debugging aid to identify bad pointers, uninitialized memory etc. You want a value that is unlikely to occur during normal execution and something that is visible when doing memory dumps or inspecting variables. Initializing to zero is less useful in this regard. I would guess that when you see people initialize to zero it is because they need to have that value at zero. A pointer with a value of 0xDEADBEEF could point to a valid memory location so it's a bad idea to use that as an alternative to NULL.