This function is used to compare the memory at the two specified locations byte-by-byte.
This function will return a value of 0 if the two memory areas are identical.
It will return a negative number if the first address contains bytes that are lower than the second memory address, or a positive number otherwise.
The absolute value of the number returned, if not zero, contains the position within each memory location of the first byte that is different (i.e. both -1 and 1 signal that the memory differs at the first byte). |