NAME
statfs - get file system statistics
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <sys/param.h>
#include <sys/mount.h>
int
statfs(const char *path, struct statfs *buf);
int
fstatfs(int fd, struct statfs *buf);
DESCRIPTION
The statfs() system call returns information about a mounted file system.
The path argument is the path name of any file within the mounted file
system. The buf argument is a pointer to a statfs structure defined as
follows:
typedef struct fsid { int32_t val[2]; } fsid_t; /* file system id type */
/*
* filesystem statistics
*/
#define MFSNAMELEN 16 /* length of type name including null */
#define MNAMELEN 88 /* size of on/from name bufs */
#define STATFS_VERSION 0x20030518 /* current version number */
struct statfs {
uint32_t f_version; /* structure version number */
uint32_t f_type; /* type of filesystem */
uint64_t f_flags; /* copy of mount exported flags */
uint64_t f_bsize; /* filesystem fragment size */
uint64_t f_iosize; /* optimal transfer block size */
uint64_t f_blocks; /* total data blocks in filesystem */
uint64_t f_bfree; /* free blocks in filesystem */
int64_t f_bavail; /* free blocks avail to non-superuser */
uint64_t f_files; /* total file nodes in filesystem */
int64_t f_ffree; /* free nodes avail to non-superuser */
uint64_t f_syncwrites; /* count of sync writes since mount */
uint64_t f_asyncwrites; /* count of async writes since mount */
uint64_t f_syncreads; /* count of sync reads since mount */
uint64_t f_asyncreads; /* count of async reads since mount */
uint64_t f_spare[10]; /* unused spare */
uint32_t f_namemax; /* maximum filename length */
uid_t f_owner; /* user that mounted the filesystem */
fsid_t f_fsid; /* filesystem id */
char f_charspare[80]; /* spare string space */
char f_fstypename[MFSNAMELEN]; /* filesystem type name */
char f_mntfromname[MNAMELEN]; /* mounted filesystem */
char f_mntonname[MNAMELEN]; /* directory on which mounted */
};
The flags that may be returned include:
MNT_RDONLY The file system is mounted read-only; Even the super-
user may not write on it.
MNT_NOEXEC Files may not be executed from the file system.
MNT_NOSUID Setuid and setgid bits on files are not honored when
they are executed.
MNT_SYNCHRONOUS All I/O to the file system is done synchronously.
MNT_ASYNC No file system I/O is done synchronously.
MNT_SOFTDEP Soft updates being done (see ffs(7)).
MNT_GJOURNAL Journaling with gjournal is enabled (see gjournal(8)).
MNT_SUIDDIR Special handling of SUID bit on directories.
MNT_UNION Union with underlying file system.
MNT_NOSYMFOLLOW Symbolic links are not followed.
MNT_NOCLUSTERR Read clustering is disabled.
MNT_NOCLUSTERW Write clustering is disabled.
MNT_MULTILABEL Mandatory Access Control (MAC) support for individual
objects (see mac(4)).
MNT_ACLS Access Control List (ACL) support enabled.
MNT_LOCAL The file system resides locally.
MNT_QUOTA The file system has quotas enabled on it.
MNT_ROOTFS Identifies the root file system.
MNT_EXRDONLY The file system is exported read-only.
MNT_NOATIME Updating of file access times is disabled.
MNT_USER The file system has been mounted by a user.
MNT_EXPORTED The file system is exported for both reading and
writing.
MNT_DEFEXPORTED The file system is exported for both reading and writing
to any Internet host.
MNT_EXPORTANON The file system maps all remote accesses to the
anonymous user.
MNT_EXKERB The file system is exported with Kerberos uid mapping.
MNT_EXPUBLIC The file system is exported publicly (WebNFS).
Fields that are undefined for a particular file system are set to -1.
The fstatfs() system call returns the same information about an open file
referenced by descriptor fd.
RETURN VALUES
Upon successful completion, the value 0 is returned; otherwise the
value -1 is returned and the global variable errno is set to indicate the
error.
ERRORS
The statfs() system call fails if one or more of the following are true:
[ENOTDIR] A component of the path prefix of path is not a
directory.
[ENAMETOOLONG] The length of a component of path exceeds 255
characters, or the length of path exceeds 1023
characters.
[ENOENT] The file referred to by path does not exist.
[EACCES] Search permission is denied for a component of the
path prefix of path.
[ELOOP] Too many symbolic links were encountered in
translating path.
[EFAULT] The buf or path argument points to an invalid address.
[EIO] An I/O error occurred while reading from or writing to
the file system.
The fstatfs() system call fails if one or more of the following are true:
[EBADF] The fd argument is not a valid open file descriptor.
[EFAULT] The buf argument points to an invalid address.
[EIO] An I/O error occurred while reading from or writing to
the file system.
SEE ALSO
fhstatfs(2)
HISTORY
The statfs() system call first appeared in 4.4BSD.