ultrix man page for ustat

ustat(2)							System Calls Manual							  ustat(2)

Name
       ustat - get file system statistics

Syntax
       #include <sys/types.h>
       #include <ustat.h>

       int ustat (dev, buf)
       dev_t dev;
       struct ustat *buf;

Description
       The  call  returns  information about a mounted file system.  The dev argument is a device number identifying a device containing a mounted
       file system.  The buf argument is a pointer to a structure that includes the following elements:
       daddr_t	f_tfree;       /* Total free blocks (Kbytes) */
       ino_t	f_tinode;      /* Number of free inodes */
       char	f_fname[512];  /* Filsys name */
       char	f_fpack[6];    /* Filsys pack name */
       The f_fpack always returns a null string.

Environment
   SYSTEM V
       Differs from System V definition in that the size of the f_fname structure element is 512 instead of 6, and the dev parameter is type dev_t
       instead of int.

Diagnostics
       The call fails if any of the following is true:

       [EINVAL]       The dev argument is not the device number of a device containing a mounted file system.

       [EFAULT]       The buf argument points outside the process's allocated address space.

       [ETIMEDOUT]    A  connect  request  or remote file operation failed, because the connected party did not properly respond after a period of
		      time that is dependent on the communications protocol.

See Also
       stat(2), fs(5)

																	  ustat(2)