dt_ident
struct dt_ident;
struct dt_ident **din_argv; /* identifiers in din_hash for arguments */
void (*di_cook)(struct dt_node *, struct dt_ident *,
void (*di_dtor)(struct dt_ident *);
size_t (*di_size)(struct dt_ident *);
struct dt_ident *di_next; /* pointer to next ident in hash chain */
struct dt_ident *, int, dtrace_actkind_t, struct dt_node *);
struct dt_ident;