# define NUM_COMMANDS 11

# define LIST 0
# define INSERT 1
# define EXIT 2
# define USE 3
# define CREATE 4
# define DELETE 5
# define QUIT 6
# define COMMIT 7
# define NEW 8
# define EXTRACT 9
# define HELP 10

# define MAX_NAME 32

typedef struct tree_node
   {
   struct tree_node *left,*right ;    /* left and right children */
   char *name, *filename ;            /* module name + file name */
   int old_offset ;                   /* offset into old file */
   int new_offset ;                   /* offset into new file */
   int length ;                       /* length of module */
   unsigned deleted : 1 ;             /* deleted flag */
   unsigned new : 1 ;                 /* new flag */
   } *tree_ptr ;

typedef struct data_node
   {
   char name[MAX_NAME] ;
   int offset ;
   } record ;

