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STATFS(2) System Calls Manual STATFS(2)

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.
November 1, 2006 Debian