get filesystem statistics
#include <unistd.h> /* libc */
#include <ustat.h> /* glibc2 */
ustat(dev_t dev, struct ustat
returns information about a mounted filesystem. dev
is a device number identifying a device containing a mounted
filesystem. ubuf is a pointer to a ustat
structure that contains the following members:
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, f_fname and f_fpack, are not
implemented and will always be filled with null bytes
zero is returned and the ustat structure pointed to
by ubuf will be filled in. On error, −1 is
returned, and errno is set appropriately.
ubuf points outside of
your accessible address space.
dev does not refer to a device containing a
The mounted filesystem referenced by dev does not
support this operation, or any version of Linux before
is deprecated and has been provided only for compatibility.
All new programs should use statfs(2) instead.
The HP-UX version of the ustat structure has an
additional field, f_blksize, that is unknown
elsewhere. HP-UX warns: For some filesystems, the number of
free inodes does not change. Such filesystems will return
−1 in the field f_tinode. For some filesystems,
inodes are dynamically allocated. Such filesystems will
return the current number of free inodes.
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