delete an element of a num_list
num_list *delnum(pthead, ptdel)
num_list *pthead, *ptdel;
Pointer to a num list
Pointer to the element to be deleted.
delnum deletes the element of the num_list pointed to by
ptdel in the list pointed to by pthead.
The list consistency is maintainded, and the element put back in the list
of free blocks.
delnum returns a pointer to the new head of list if the ptdel
pointer used to belong to the list. In most case, it has the value of
pthead. If the pointer doesn't belong to the list, NULL is returned.
"*** mbk error *** delnum impossible : pointer NULL"
At least one of the arguments are pointing to NULL, and that clear that
such a pointer can't be deleted.
void delete_match(c0, c1)
num_list *c1, *c2;
num_list *t0, *t1, *next;
for (t0 = c0; t0; t0 = next)
for (t1 = c1; t1; t1 = t1->NEXT)
if (t1->DATA == t0->DATA)
next = delnum(c0, t0);