NAME
statfs
—
get file system statistics
LIBRARY
library “libc”
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
Thestatfs
()
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 1024 /* size of on/from name bufs */ #define STATFS_VERSION 0x20140518 /* 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
HISTORY
The statfs
() system call first appeared in
4.4BSD.