void qsort(void *base, int num, int size, sort_comparator comparator);
void *base
Array first pointer
int num
The length of the array, the best practice is sizeof(array) / sizeof(elemType)
int size
Size of array element, the best practice is sizeof(elemType)
sort_comparator comparator
A comparator between two given elements, if the element type is number, the best practice is a - b.