How to pass a structure to a function

[zolfaghar]

I have the following code ...

#include <stdio.h>
int main (void)
{
struct book
  {
    char name[25];
    char author [25];
    int callno;
  };
struct book b1 = { "Moubidick", "Ansari,Shahin", 101};
display (b1);
}
display (struct book b)
{
  printf ("\n Here is the book information %s %s %d", b.name, b.author, b.callno);
}
~

And I get the following warnings: 

struct3.c:14:17: warning: 'struct book' declared inside parameter list
 display (struct book b)
                 ^
struct3.c:14:17: warning: its scope is only this definition or declaration, which is probably not what you want
struct3.c:14:22: error: parameter 1 ('b') has incomplete type
 display (struct book b)
                      ^

I looked around online, and I believe the warnings are for not declaring the variable b earlier in the main. Is that right?
I like to know if what I am doing is the best way to go about passing a structure to a function. It is not my code; I am following a text and it may be that the author is trying to teach something, which he'll build on later.

[Elkvis]

You declared your struct inside your main function. Display has no way to know of its existence. Move your struct declaration to somewhere both main and display can see it, as a first step.

[zolfaghar]

Thanks. It compiled without error.