STATFS(2) BSD System Calls Manual STATFS(2)NAME
statfs, fstatfs — 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);
DESCRIPTIONStatfs() returns information about a mounted file system. Path is the
path name of any file within the mounted filesystem. Buf is a pointer to
a statfs() structure defined as follows:
typedef struct fsid { int32_t val[2]; } fsid_t; /* file system id type */
/*
* file system statistics
*/
#define MFSNAMELEN 16 /* length of fs type name, including null */
#define MNAMELEN 90 /* length of buffer for returned name */
struct statfs {
long f_bsize; /* fundamental file system block size */
long f_iosize; /* optimal transfer block size */
long f_blocks; /* total data blocks in file system */
long f_bfree; /* free blocks in fs */
long f_bavail; /* free blocks avail to non-superuser */
long f_files; /* total file nodes in file system */
long f_ffree; /* free file nodes in fs */
fsid_t f_fsid; /* file system id */
uid_t f_owner; /* user that mounted the filesystem */
int f_type; /* type of filesystem */
int f_flags; /* copy of mount flags */
long f_syncwrites; /* count of sync writes since mount */
long f_asyncwrites; /* count of async writes since mount */
char f_fstypename[MFSNAMELEN];/* fs type name */
char f_mntonname[MNAMELEN]; /* mount point */
long f_syncreads; /* count of sync reads since mount */
long f_asyncreads; /* count of async reads since mount */
char f_mntfromname[MNAMELEN]; /* mounted filesystem */
};
The flags that may be returned include:
MNT_RDONLY The filesystem is mounted read-only; Even the super-user
may not write on it.
MNT_NOEXEC Files may not be executed from the filesystem.
MNT_NOSUID Setuid and setgid bits on files are not honored when
they are executed.
MNT_NODEV Special files in the filesystem may not be opened.
MNT_SYNCHRONOUS All I/O to the filesystem is done synchronously.
MNT_ASYNC No filesystem I/O is done synchronously.
MNT_LOCAL The filesystem resides locally.
MNT_QUOTA The filesystem has quotas enabled on it.
MNT_ROOTFS Identifies the root filesystem.
MNT_EXRDONLY The filesystem is exported read-only.
MNT_EXPORTED The filesystem is exported for both reading and writing.
MNT_DEFEXPORTED The filesystem is exported for both reading and writing
to any Internet host.
MNT_EXPORTANON The filesystem maps all remote accesses to the anonymous
user.
MNT_EXKERB The filesystem is exported with Kerberos uid mapping.
Fields that are undefined for a particular file system are set to -1.
Fstatfs() 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.
ERRORSStatfs() fails if one or more of the following are true:
[ENOTDIR] A component of the path prefix of path is not a direc‐
tory.
[ENAMETOOLONG] The length of a component of path exceeds 255 charac‐
ters, 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 translat‐
ing path.
[EFAULT] Buf or path points to an invalid address.
[EIO] An I/O error occurred while reading from or writing to
the file system.
Fstatfs() fails if one or more of the following are true:
[EBADF] fd is not a valid open file descriptor.
[EFAULT] Buf points to an invalid address.
[EIO] An I/O error occurred while reading from or writing to
the file system.
SEE ALSOstat(2), statvfs(2)HISTORY
The statfs() function first appeared in 4.4BSD.
BSD September 28, 2008 BSD
