Section: Linux Programmer's Manual (2)
ustat - get filesystem statistics
#include <unistd.h> /* libc */
#include <ustat.h> /* glibc2 */
int ustat(dev_t dev, struct ustat *ubuf);
returns information about a mounted filesystem.
is a device number identifying a device containing
a mounted filesystem.
is a pointer to a
structure that contains the following
daddr_t f_tfree; /* Total free blocks */
ino_t f_tinode; /* Number of free inodes */
char f_fname; /* Filsys name */
char f_fpack; /* Filsys pack name */
The last two fields,
are not implemented and will
always be filled with null bytes ('\0').
On success, zero is returned and the
structure pointed to by
will be filled in.
On error, -1 is returned, and
is set appropriately.
points outside of your accessible address space.
does not refer to a device containing a mounted filesystem.
The mounted filesystem referenced by
does not support this operation, or any version of Linux before
Since version 2.28, glibc no longer provides a wrapper for this system call.
is deprecated and has been provided only for compatibility.
All new programs should use
The HP-UX version of the
structure has an additional field,
that is unknown elsewhere.
For some filesystems, the number of free inodes does not change.
Such filesystems will return -1 in the field
For some filesystems, inodes are dynamically allocated.
Such filesystems will return the current number of free inodes.
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