push,pop, & print a stack

I have been working on this program for 3 days and can't get anywhere.  I have to interactively ask if the user wants to add, or remove from the stack and print the contents.  I can push function seems to be working, but when I print, I only get the top number on the stack when I need to print the entire contents.  Here is my code so far:
#include<stdio.h>
#include<stdlib.h>
typedef struct node node_t;
typedef node_t *ptr_t;
struct node
   {
    int n;
    ptr_t next;
   };
ptr_t head=NULL;
void pop(void);
void push(void);
ptr_t newnode(void);
void choice(void);
void error(void);
void printstk(void);

void main(void)
{
   choice();
}

void choice(void)
{

   int choice;
   do
   {
   printf("This program will allow you to add or remove the first item\n");
   printf("of the stack.\n1-Add item\n2-Remove item\n3-Quit\nYour choice: ");
   scanf("%d",&choice);

    switch (choice)
       { case 1:
            push();
            printstk();
            break;
       case 2:
            pop();
            break;
       case 3:
            printf("Thank You");
       default:
           printf("Please enter your choice again");
       }
    }
   while (choice!=3);
}

ptr_t newnode(void)
{
    return (ptr_t)calloc(1,sizeof(node_t));
}
void push(void)
{
      int ans;
      ptr_t p;
      do
       {
      printf("\nEnter a number: ");
      scanf("%d",&p->n);
      p->next=NULL;
      head=p;
      printf("Enter more?\n1--Yes\n2--No\nChoice: ");
      scanf("%d",&ans);
       }
     while (ans==1);
}


void printstk(void)
{
      ptr_t p;
      p=head;
      while (p!=NULL)
         {
           printf("%d\t",p->n);
           p=p->next;
           free(p);
         }
}

void pop(void)
{
      ptr_t p;
      head=head->next;
      free(p);
     printstk();
}

Thanks!!!