Describe how the signal() operation associated with monitors differs from the corresponding operation defined for semaphores. typedef struct node { value_t data; struct node *next; } Node; Node top;...

Extracted text: Describe how the signal() operation associated with monitors differs from the corresponding operation defined for semaphores. typedef struct node { value_t data; struct node *next; } Node; Node top; // top of stack void push(value_t item) { Node *old_node; Node *new_node; new node = malloc(sizeof (Node)): new_node->data = item; do old node = top; new node->next = old_node; while (compare_and swap(top,old_node,new_node) != old node); } value_t pop() { Node *old node; Node *new_node; do { old node = top; if (old_node == NULL) return NULL; new node = old node->next; } while (compare_and_swap(top,old_node,new_node) != old_node); return old. node->data: } Figure 6.18 Lock-free stack for Exercise 6.15.