.\" Modified 2003-08-17 by Walter Harms
.\" Modified 2004-06-23 by Michael Kerrisk <mtk.manpages@gmail.com>
.\"
-.TH STATFS 2 2010-11-21 "Linux" "Linux Programmer's Manual"
+.TH STATFS 2 2014-06-13 "Linux" "Linux Programmer's Manual"
.SH NAME
statfs, fstatfs \- get filesystem statistics
.SH SYNOPSIS
ADFS_SUPER_MAGIC 0xadf5
AFFS_SUPER_MAGIC 0xADFF
+ BDEVFS_MAGIC 0x62646576
BEFS_SUPER_MAGIC 0x42465331
BFS_MAGIC 0x1BADFACE
+ BINFMTFS_MAGIC 0x42494e4d
+ BTRFS_SUPER_MAGIC 0x9123683E
+ CGROUP_SUPER_MAGIC 0x27e0eb
CIFS_MAGIC_NUMBER 0xFF534D42
CODA_SUPER_MAGIC 0x73757245
COH_SUPER_MAGIC 0x012FF7B7
CRAMFS_MAGIC 0x28cd3d45
+ DEBUGFS_MAGIC 0x64626720
DEVFS_SUPER_MAGIC 0x1373
+ DEVPTS_SUPER_MAGIC 0x1cd1
+ EFIVARFS_MAGIC 0xde5e81e4
EFS_SUPER_MAGIC 0x00414A53
EXT_SUPER_MAGIC 0x137D
EXT2_OLD_SUPER_MAGIC 0xEF51
EXT2_SUPER_MAGIC 0xEF53
EXT3_SUPER_MAGIC 0xEF53
EXT4_SUPER_MAGIC 0xEF53
+ FUSE_SUPER_MAGIC 0x65735546
+ FUTEXFS_SUPER_MAGIC 0xBAD1DEA
HFS_SUPER_MAGIC 0x4244
+ HOSTFS_SUPER_MAGIC 0x00c0ffee
HPFS_SUPER_MAGIC 0xF995E849
HUGETLBFS_MAGIC 0x958458f6
ISOFS_SUPER_MAGIC 0x9660
MINIX_SUPER_MAGIC2 0x138F /* 30 char minix */
MINIX2_SUPER_MAGIC 0x2468 /* minix V2 */
MINIX2_SUPER_MAGIC2 0x2478 /* minix V2, 30 char names */
+ MINIX3_SUPER_MAGIC 0x4d5a /* minix V3 fs, 60 char names */
+ MQUEUE_MAGIC 0x19800202
MSDOS_SUPER_MAGIC 0x4d44
NCP_SUPER_MAGIC 0x564c
NFS_SUPER_MAGIC 0x6969
+ NILFS_SUPER_MAGIC 0x3434
NTFS_SB_MAGIC 0x5346544e
OPENPROM_SUPER_MAGIC 0x9fa1
+ PIPEFS_MAGIC 0x50495045
PROC_SUPER_MAGIC 0x9fa0
+ PSTOREFS_MAGIC 0x6165676C
QNX4_SUPER_MAGIC 0x002f
+ QNX6_SUPER_MAGIC 0x68191122
+ RAMFS_MAGIC 0x858458f6
REISERFS_SUPER_MAGIC 0x52654973
ROMFS_MAGIC 0x7275
+ SELINUX_MAGIC 0xf97cff8c
+ SMACK_MAGIC 0x43415d53
SMB_SUPER_MAGIC 0x517B
+ SOCKFS_MAGIC 0x534F434B
+ SQUASHFS_MAGIC 0x73717368
+ SYSFS_MAGIC 0x62656572
SYSV2_SUPER_MAGIC 0x012FF7B6
SYSV4_SUPER_MAGIC 0x012FF7B5
TMPFS_MAGIC 0x01021994
UDF_SUPER_MAGIC 0x15013346
UFS_MAGIC 0x00011954
USBDEVICE_SUPER_MAGIC 0x9fa2
+ V9FS_MAGIC 0x01021997
VXFS_SUPER_MAGIC 0xa501FCF5
+ XENFS_SUPER_MAGIC 0xabba1974
XENIX_SUPER_MAGIC 0x012FF7B4
XFS_SUPER_MAGIC 0x58465342
_XIAFS_SUPER_MAGIC 0x012FD16D
.fi
.in
.PP
+Most of these MAGIC constants are defined in
+.I /usr/include/linux/magic.h
+some are hardcoded in kernel sources.
+.PP
Nobody knows what
.I f_fsid
is supposed to contain (but see below).
contains some random stuff such that the pair
.RI ( f_fsid , ino )
uniquely determines a file.
-Some operating systems use (a variation on) the device number, or the device number
-combined with the filesystem type.
-Several OSes restrict giving out the
+Some operating systems use (a variation on) the device number,
+or the device number combined with the filesystem type.
+Several operating systems restrict giving out the
.I f_fsid
field to the superuser only (and zero it for unprivileged users),
because this field is used in the filehandle of the filesystem
when NFS-exported, and giving it out is a security concern.
.LP
-Under some operating systems the
+Under some operating systems, the
.I fsid
-can be used as second argument to the
+can be used as the second argument to the
.BR sysfs (2)
system call.
+.SH BUGS
+From Linux 2.6.38 up to and including Linux 3.1,
+.\" broken in commit ff0c7d15f9787b7e8c601533c015295cc68329f8
+.\" fixed in commit d70ef97baf048412c395bb5d65791d8fe133a52b
+.BR fstatfs ()
+failed with the error
+.B ENOSYS
+for file descriptors created by
+.BR pipe (2).
.SH SEE ALSO
.BR stat (2),
.BR statvfs (2),
.BR path_resolution (7)
.SH COLOPHON
-This page is part of release 3.68 of the Linux
+This page is part of release 3.75 of the Linux
.I man-pages
project.
A description of the project,
OSDN Git Service
