UNIX 6th Ed. - /usr/sys/filsys.h

   1: /*
   2:  * Definition of the unix super block.
   3:  * The root super block is allocated and
   4:  * read in iinit/alloc.c. Subsequently
   5:  * a super block is allocated and read
   6:  * with each mount (smount/sys3.c) and
   7:  * released with unmount (sumount/sys3.c).
   8:  * A disk block is ripped off for storage.
   9:  * See alloc.c for general alloc/free
  10:  * routines for free list and I list.
  11:  */
  12: struct  filsys
  13: {
  14:     int s_isize;    /* size in blocks of I list */
  15:     int s_fsize;    /* size in blocks of entire volume */
  16:     int s_nfree;    /* number of in core free blocks (0-100) */
  17:     int s_free[100];    /* in core free blocks */
  18:     int s_ninode;   /* number of in core I nodes (0-100) */
  19:     int s_inode[100];   /* in core free I nodes */
  20:     char    s_flock;    /* lock during free list manipulation */
  21:     char    s_ilock;    /* lock during I list manipulation */
  22:     char    s_fmod;     /* super block modified flag */
  23:     char    s_ronly;    /* mounted read-only flag */
  24:     int s_time[2];  /* current date of last update */
  25:     int pad[50];
  26: };

Defined struct's

Usage of this include