Stack with Linked List

//STACK WITH linked list

#include<stdlib.h>
#include<limits.h>
#include<conio.h>
#include<stdio.h>

struct StackNode {
    int data;
    struct StackNode* next;
};

struct StackNode* newNode(int data)
{
    struct StackNode* node = (struct StackNode*) malloc(sizeof(struct StackNode));
    node->data = data;
    return node;

}

int isEmpty(struct StackNode* root)
{
    return !root;
}

void push(struct StackNode** root, int item)
{
    struct StackNode* node = newNode(item);
    node->next = *root;

    *root = node;
    printf("pushed %d \n", item);

}

void pop(struct StackNode** root)
{
    if (isEmpty(*root))
    {
        printf("Underflow \n");
        return;
    }
    int poped = (*root)->data;
    struct StackNode* temp = *root;
    *root = (*root)->next;
    free(temp);

    printf("popped %d\n", poped);

}

void peek(struct StackNode* root)
{
    if (isEmpty(root))
    {
        printf("empty stack \n");
        return;
    }
    printf("peeked %d \n" , root->data);

}


int main()
{
    struct StackNode* stackRoot = NULL;
    push(&stackRoot, 4);
    push(&stackRoot, 6);

    pop(&stackRoot);

    peek(stackRoot);

    pop(&stackRoot);
    peek(stackRoot);
    push(&stackRoot, 6);
    peek(stackRoot);

    getchar();
    return 0;


}