statfs (2)
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NAME
statfs - get file system statisticsLIBRARY
Lb libcSYNOPSIS
In sys/param.h In sys/mount.h Ft int Fn statfs const char *path struct statfs *buf Ft int Fn fstatfs int fd struct statfs *bufDESCRIPTION
The Fn 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.
- 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 Fn fstatfs system call returns the same information about an open file referenced by descriptor Fa fd .
RETURN VALUES
Rv -stdERRORS
The Fn 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 Fn 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.