ustat(2) System Calls Manual ustat(2)
NAME
ustat - get filesystem statistics
LIBRARY
Standard C library (libc, -lc)
SYNOPSIS
#include <sys/types.h>
#include <unistd.h> /* libc[45] */
#include <ustat.h> /* glibc2 */
[[deprecated]] int ustat(dev_t dev, struct ustat *ubuf);
DESCRIPTION
ustat() returns information about a mounted filesystem. dev is a de-
vice number identifying a device containing a mounted filesystem. ubuf
is a pointer to a ustat structure that contains the following members:
daddr_t f_tfree; /* Total free blocks */
ino_t f_tinode; /* Number of free inodes */
char f_fname[6]; /* Filsys name */
char f_fpack[6]; /* Filsys pack name */
The last two fields, f_fname and f_fpack, are not implemented and will
always be filled with null bytes ('\0').
RETURN VALUE
On success, zero is returned and the ustat structure pointed to by ubuf
will be filled in. On error, -1 is returned, and errno is set to indi-
cate the error.
ERRORS
EFAULT ubuf points outside of your accessible address space.
EINVAL dev does not refer to a device containing a mounted filesystem.
ENOSYS The mounted filesystem referenced by dev does not support this
operation, or any version of Linux before Linux 1.3.16.
STANDARDS
None.
HISTORY
SVr4. Removed in glibc 2.28.
ustat() is deprecated and has been provided only for compatibility.
All new programs should use statfs(2) instead.
HP-UX notes
The HP-UX version of the ustat structure has an additional field,
f_blksize, that is unknown elsewhere. HP-UX warns: For some filesys-
tems, the number of free inodes does not change. Such filesystems will
return -1 in the field f_tinode. For some filesystems, inodes are dy-
namically allocated. Such filesystems will return the current number
of free inodes.
SEE ALSO
stat(2), statfs(2)
Linux man-pages 6.7 2023-10-31 ustat(2)
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