struct node{
   int value;
   struct node* next;
};

void addFirst(struct node *list, int value){
    struct node *new_node = (struct node*) malloc (sizeof (struct node));
    new_node->value = value;
    new_node->next = list;
    list = new_node;
   }

struct node *my_list = null;
addFirst((struct node *)&my_list, 123);

void addFirst(struct node *list, int value){
    struct node **real_list = (struct node **)list;
    struct node *new_node = (struct node*) malloc (sizeof (struct node));
    new_node->value = value;
    new_node->next = *real_list;
    *real_list = new_node;

void addFirst(struct node **list, int value){
    struct node *new_node = (struct node*) malloc (sizeof (struct node));
    new_node->value = value;
    new_node->next = *list;
    *list = new_node;
}

struct node * addFirst(struct node *list, int value){
    struct node *new_node = (struct node*) malloc (sizeof (struct node));
    new_node->value = value;
    new_node->next = list;
    return new_node;
}

head = addfirst(head,45);

void addFirst(struct node **list, int value){
    struct node *new_node = (struct node*) malloc (sizeof (struct node));
    new_node->value = value;
    new_node->next = *list;
    *list = new_node;
}

void addFirst(struct node **list, int value){
     struct node *new_node = (struct node*) malloc (sizeof (struct node));
     new_node->value = value;
     new_node->next = *list;
     *list = new_node;
}

addFirst(&list, value);

struct node *head;

void addFirst(struct node *list, int value){
     struct node *new_node = (struct node*) malloc (sizeof (struct node));
     new_node->value = value;
     new_node->next = list->next;
     list->next = new_node;
}

addFirst(head, 45);