STATFS(2) | FreeBSD System Calls Manual | STATFS(2) |
NAME
statfs — get file system statisticsLIBRARY
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.November 1, 2006 | FreeBSD |