#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
Fa path
argument
is the path name of any file within the mounted file system.
The
Fa buf
argument
is a pointer to a
Vt 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.
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
Fa fd .
RETURN VALUES
Rv -std
ERRORS
The
statfs ();
system call
fails if one or more of the following are true:
Bq Er ENOTDIR
A component of the path prefix of
Fa path
is not a directory.
Bq Er ENAMETOOLONG
The length of a component of
Fa path
exceeds 255 characters,
or the length of
Fa path
exceeds 1023 characters.
Bq Er ENOENT
The file referred to by
Fa path
does not exist.
Bq Er EACCES
Search permission is denied for a component of the path prefix of
Fa path .
Bq Er ELOOP
Too many symbolic links were encountered in translating
Fa path .
Bq Er EFAULT
The
Fa buf
or
Fa path
argument
points to an invalid address.
Bq Er 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:
Bq Er EBADF
The
Fa fd
argument
is not a valid open file descriptor.
Bq Er EFAULT
The
Fa buf
argument
points to an invalid address.
Bq Er EIO
An
I/O
error occurred while reading from or writing to the file system.
