statvfs(2) SYSTEM CALLS 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 lead-
ing to the file must be searchable.
The statvfs structure pointed to by buf includes the follow-
ing 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).
The following flags can be returned in the fflag field:
STRDONLY 0x01 /* read-only file system */
STNOSUID 0x02 /* does not support setuid/setgid
semantics */
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statvfs(2) SYSTEM CALLS statvfs(2)
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 multi-
ple 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.
EINTR A signal was caught during fstatvfs execu-
tion.
EIO An I/O error occurred while reading the file
system.
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statvfs(2) SYSTEM CALLS statvfs(2)
DIAGNOSTICS
Upon successful completion a value of 0 is returned. Other-
wise, 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).
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