1) need to add routine to gridfile to delete pages in the file.
2) Page allocation wil be done via buffer manager routines:

   //allocate new page
   Status newpage (int &pageno, Page *& page);

   //return page to free pool
   Status freePage (int pageno);
     
   //read and pin page 
   Status pinPage (int pageno, Page *& page);
    
   //write and unpin page
   Status unpinPage (int pageno, int dirty);

3) DB routines keep track of header page

   // DB remember first page of file
   Status set_first_page (char *name, int pageno);

   // DB forget first page of file
   Status drop_first_page (char *name);

4) to start a file:
    newPage
    set_first_page

5) open existing file:
    get_first_page

6) Page class: how to access data on page:

   class Page {
    LSN lsn;
    char data[0];
    }

   then access methods derive the class as follows:
   class mypage: Page
     {mydata.....
     }