statvfs(2) statvfs(2)
NAME
statvfs, fstatvfs - get file system information
SYNOPSIS
#include <sys/types.h>
#include <sys/statvfs.h>
int statvfs (const char *path, struct statvfs *buf);
int fstatvfs (int fildes, struct statvfs *buf);
DESCRIPTION
statvfs returns a ``generic superblock'' describing a file system; it
can be used to acquire information about mounted file systems. buf
is a pointer to a structure (described below) that is filled by the
system call.
path should name a file that resides on that file system. The file
system type is known to the operating system. Read, write, or
execute permission for the named file is not required, but all
directories listed in the path name leading to the file must be
searchable.
The statvfs structure pointed to by buf includes the following
members:
ulong fbsize; /* preferred file system block size */
ulong ffrsize; /* fundamental filesystem block size
(if supported) */
ulong fblocks; /* total # of blocks on file system
in units of ffrsize */
ulong fbfree; /* total # of free blocks */
ulong fbavail; /* # of free blocks avail to
non-superuser */
ulong ffiles; /* total # of file nodes (inodes) */
ulong fffree; /* total # of free file nodes */
ulong ffavail; /* # of inodes avail to
non-superuser*/
fsidt ffsid; /* file system id (dev for now) */
char fbasetype[FSTYPSZ]; /* target fs type name,
null-terminated */
ulong fflag; /* bit mask of flags */
ulong fnamemax; /* maximum file name length */
char ffstr[32]; /* file system specific string */
ulong ffiller[16]; /* reserved for future expansion */
fbasetype contains a null-terminated FSType name of the mounted
target (e.g. s5 mounted over rfs will contain s5).
7/91 Page 1
statvfs(2) statvfs(2)
The following flags can be returned in the fflag field:
STRDONLY 0x01 /* read-only file system */
STNOSUID 0x02 /* does not support setuid/setgid
semantics */
STNOTRUNC 0x04 /* does not truncate file names
longer than {NAMEMAX}*/
fstatvfs is similar to statvfs, except that the file named by path in
statvfs is instead identified by an open file descriptor fildes
obtained from a successful open, creat, dup, fcntl, or pipe system
call.
statvfs fails if one or more of the following are true:
EACCES Search permission is denied on a component of the path
prefix.
EFAULT path or buf points outside the process's allocated
address space.
EINTR A signal was caught during statvfs execution.
EIO An I/O error occurred while reading the file system.
ELOOP Too many symbolic links were encountered in
translating path.
EMULTIHOP Components of path require hopping to multiple remote
machines and file system type does not allow it.
ENAMETOOLONG The length of a path component exceeds {NAMEMAX}
characters, or the length of path exceeds {PATHMAX}
characters.
ENOENT Either a component of the path prefix or the file
referred to by path does not exist.
ENOLINK path points to a remote machine and the link to that
machine is no longer active.
ENOTDIR A component of the path prefix of path is not a
directory.
fstatvfs fails if one or more of the following are true:
EFAULT buf points to an invalid address.
EBADF fildes is not an open file descriptor.
Page 2 7/91
statvfs(2) statvfs(2)
EINTR A signal was caught during fstatvfs execution.
EIO An I/O error occurred while reading the file system.
DIAGNOSTICS
Upon successful completion a value of 0 is returned. Otherwise, a
value of -1 is returned and errno is set to indicate the error.
SEE ALSO
chmod(2), chown(2), creat(2), link(2), mknod(2), pipe(2), read(2),
time(2), unlink(2), utime(2), write(2).
7/91 Page 3