4.3BSD - /usr/src/etc/dump.4.1/include.4.1/sys/fblk.h

   1: /*	fblk.h	4.2	81/02/19	*/
   2: 
   3: struct fblk
   4: {
   5:     int     df_nfree;
   6:     daddr_t df_free[NICFREE];
   7: };

Defined struct's

Usage of this include