// Here is how I defined booknode
typedef struct booknode
{
	char *title;			// char[], holds book title 
	char *author;			// char[], holds book author
	char *isbn;				// char[], holds book isbn
    float price;			// float, holds sales price of book
    struct booknode *next;  // Pointer to next booknode
} BOOKNODE;

void initializebookdata( void )
{
	// Get memory for first book node
	BOOKNODE *firstbook = (BOOKNODE*) malloc(sizeof(BOOKNODE));
 
	headptr = firstbook;	// Set the head pointer equal to the first book node memory
 
	// Add the first books data
	firstbook->title = "All the King's Men";
	firstbook->author = "Robert Penn Warren";
	firstbook->isbn = "0156004801";
	firstbook->price = 13.46F;
	// Get memory for second book node
	BOOKNODE *secondbook = (BOOKNODE*) malloc(sizeof(BOOKNODE));
	firstbook->next = secondbook;
 
	secondbook->title = "The C++ Programming Language (Special 3rd Edition)";
	secondbook->author = "Bjarne Stroustrup";
	secondbook->isbn = "0201700735";
	secondbook->price = 54.34F;
	// Get memory for third book node
	BOOKNODE *thirdbook = (BOOKNODE*) malloc(sizeof(BOOKNODE));
	secondbook->next = thirdbook;			
 
	thirdbook->title = "The C++ Standard Library : A Tutorial and Reference";
	thirdbook->author = "Nicolai M. Josuttis";
	thirdbook->isbn = "0201379260";
	thirdbook->price = 51.19F;
	// Get memory for fourth book node
	BOOKNODE *forthbook = (BOOKNODE*) malloc(sizeof(BOOKNODE));
	thirdbook->next = forthbook;			
 
	forthbook->title = "C++ Primer (4th Edition)";
	forthbook->author = "Stanley B. Lippman, Josée Lajoie, Barbara E. Moo";
	forthbook->isbn = "0201721481";
	forthbook->price = 32.99F;
	forthbook->next = 0;			// Mark it end of node list
}

int displayinventory( void )
{
	int s=0;			// User's selection
	int i=1;			// Counter.  Starts at one to display number for user to make selection
	wkptr = headptr;	// Used to walk the structure
 
	// Start endless loop.  Break out when user entered valid input
	while (1)	// Start of while()
	{
		clrscr();	// Clear the console's screen
 
		// Print out the title of this screen to user
		printf("%s", INVENTORYTITLE);	
 
		while( wkptr != 0)	// Start while loop.
		{
			// Print inventory line
			printf("%d: %s\n   By: %s - %s - %0.2f\n\n", (i++), wkptr->title, wkptr->author, wkptr->isbn, wkptr->price );
			wkptr = wkptr->next;	// Advance pointer to next address in list
		}	// End while()
 
		// Print user instructions.  Use i-1 to display the upper choice limit
		printf("Enter 1-%d or (-1) to return to main menu: ", i-1);
		scanf("%d", &s);	// Scan input into s
 
		// Test for valid answer
		if ( ( s == -1 ) || ( ( s > 0 ) && ( s<i ) ) )	// Valid response
		{
			break;	// break out of endless while()
		}
		else	// Invalid response.  Reset everything and start again
		{
			i=1;				// Counter.  Starts at one to display number for user to make selection
			wkptr = headptr;	// Used to walk the structure
		} 
	}	// End while()
 
	return s;	// Return users input which is in variable s
}

void getBookData(void)
{
	BOOKNODE *newbook = (BOOKNODE*) malloc(sizeof(BOOKNODE));
	wkptr = headptr;					// Used to control the while loop
	clrscr();	// Clear the console's screen
	char booktitle[256];
	char author[256];
	char isbn[15];
	float price = 0.0F;
	cout << MENU2TITLE;
 
	// Get books data
	cout << "Please enter books title: ";
	cin.getline(booktitle, 256);
	cout << "Please enter books author: ";
	cin.getline(author, 256);
	cout << "Please enter books ISBN: ";
	cin.getline(isbn, 15);
	cout << "Please enter books price:  $[00.00] ";
	cin >> price;
 
	newbook->title=booktitle;
	newbook->author=author;
	newbook->isbn=isbn;
	newbook->price=price;
	newbook->next=0;
	// Add Book to end of link list 
	if ( wkptr == 0 )					// First one on the list
	{
		wkptr->next = newbook;
	}
	else								// Have other books
	{
		while ( wkptr->next != 0 )		// Find the end of the list
		{
			wkptr = wkptr->next;
		}
		wkptr->next = newbook;			// Last on the list so point to new book
	}
//	addinventory(booktitle, author, isbn, price);
}