1.\" $NetBSD: statvfs.5,v 1.16 2021/10/21 13:21:53 andvar Exp $ 2.\" 3.\" Copyright (c) 1989, 1991, 1993 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. Neither the name of the University nor the names of its contributors 15.\" may be used to endorse or promote products derived from this software 16.\" without specific prior written permission. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 19.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 22.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28.\" SUCH DAMAGE. 29.\" 30.\" @(#)statfs.2 8.5 (Berkeley) 5/24/95 31.\" 32.Dd September 22, 2019 33.Dt STATVFS 5 34.Os 35.Sh NAME 36.Nm statvfs 37.Nd file system statistics 38.Sh SYNOPSIS 39.In sys/types.h 40.In sys/statvfs.h 41.Sh DESCRIPTION 42The 43.In sys/statvfs.h 44header defines the structures and functions that 45return information about a mounted file system. 46The 47.Nm statvfs 48structure is defined as follows: 49.Bd -literal 50typedef struct { int32_t val[2]; } fsid_t; /* file system id type */ 51 52#define VFS_NAMELEN 32 /* length of fs type name, including nul */ 53#define VFS_MNAMELEN 1024 /* length of buffer for returned name */ 54 55struct statvfs { 56 unsigned long f_flag; /* copy of mount exported flags */ 57 unsigned long f_bsize; /* system block size */ 58 unsigned long f_frsize; /* system fragment size */ 59 unsigned long f_iosize; /* optimal file system block size */ 60 61 /* The following are in units of f_frsize */ 62 fsblkcnt_t f_blocks; /* number of blocks in file system */ 63 fsblkcnt_t f_bfree; /* free blocks avail in file system */ 64 fsblkcnt_t f_bavail; /* free blocks avail to non-root */ 65 fsblkcnt_t f_bresvd; /* blocks reserved for root */ 66 67 fsfilcnt_t f_files; /* total file nodes in file system */ 68 fsfilcnt_t f_ffree; /* free file nodes in file system */ 69 fsfilcnt_t f_favail /* free file nodes avail to non-root */ 70 fsfilcnt_t f_fresvd; /* file nodes reserved for root */ 71 72 uint64_t f_syncreads; /* count of sync reads since mount */ 73 uint64_t f_syncwrites; /* count of sync writes since mount */ 74 75 uint64_t f_asyncreads; /* count of async reads since mount */ 76 uint64_t f_asyncwrites; /* count of async writes since mount */ 77 78 unsigned long f_fsid; /* POSIX compliant file system id */ 79 fsid_t f_fsidx; /* NetBSD compatible file system id */ 80 81 unsigned long f_namemax; /* maximum filename length */ 82 uid_t f_owner; /* user that mounted the file system */ 83 84 uint64_t f_spare[4]; /* spare space */ 85 86 char f_fstypename[VFS_NAMELEN]; /* fs type name */ 87 char f_mntonname[VFS_MNAMELEN]; /* directory on which mounted */ 88 char f_mntfromname[VFS_MNAMELEN]; /* mounted file system */ 89 char f_mntfromlabel[_VFS_MNAMELEN]; /* disk label name if avail */ 90}; 91.Ed 92.Pp 93The 94.Fa f_flag 95argument can have the following bits set: 96.Bl -tag -width ST_SYNCHRONOUS 97.It Dv ST_RDONLY 98The filesystem is mounted read-only; 99Even the super-user may not write on it. 100.It Dv ST_NOEXEC 101Files may not be executed from the filesystem. 102.It Dv ST_NOSUID 103Setuid and setgid bits on files are not honored when they are executed. 104.It Dv ST_NODEV 105Special files in the filesystem may not be opened. 106.It Dv ST_UNION 107Union with underlying filesystem instead of obscuring it. 108.It Dv ST_SYNCHRONOUS 109All I/O to the filesystem is done synchronously. 110.It Dv ST_ASYNC 111No filesystem I/O is done synchronously. 112.It Dv ST_NOCOREDUMP 113Don't write core dumps to this file system. 114.It Dv ST_NOATIME 115Never update access times. 116.It Dv ST_SYMPERM 117Recognize symbolic link permission. 118.It Dv ST_NODEVMTIME 119Never update modification times for device files. 120.It Dv ST_LOG 121Use logging (journaling). 122.It Dv ST_LOCAL 123The filesystem resides locally. 124.It Dv ST_QUOTA 125The filesystem has quotas enabled on it. 126.It Dv ST_ROOTFS 127Identifies the root filesystem. 128.It Dv ST_EXRDONLY 129The filesystem is exported read-only. 130.It Dv ST_EXPORTED 131The filesystem is exported for both reading and writing. 132.It Dv ST_DEFEXPORTED 133The filesystem is exported for both reading and writing to any Internet host. 134.It Dv ST_EXPORTANON 135The filesystem maps all remote accesses to the anonymous user. 136.It Dv ST_EXKERB 137The filesystem is exported with Kerberos uid mapping. 138.It Dv ST_EXNORESPORT 139Don't enforce reserved ports (NFS). 140.It Dv ST_EXPUBLIC 141Public export (WebNFS). 142.El 143.Pp 144Fields that are undefined for a particular file system are set to \-1. 145.Sh NOTES 146.Bl -tag -width f_bavail 147.It f_flag 148The 149.Fa f_flag 150field is the same as the 151.Fa f_flags 152field in the 153.Bx 4.3 154.Ic statfs 155system call. 156.It f_fsid 157Is defined to be 158.Ft unsigned long 159by the X/Open standard. 160Unfortunately this is not enough space to store our 161.Ft fsid_t , 162so we define an additional 163.Fa f_fsidx 164field. 165.It f_bavail 166Could historically be negative (in the 167.Ic statfs 168system call) when the used space has exceeded 169the non-superuser free space. 170In order to comply with the X/Open standard, we have to define 171.Ft fsblkcnt_t 172as an unsigned type, so in all cases where 173.Fa f_bavail 174would have been negative, we set it to 0. 175In addition we provide 176.Fa f_bresvd 177which contains the amount of reserved blocks for the superuser, so 178the old value of 179.Fa f_bavail 180can be easily computed as: 181.Bd -literal 182 old_bavail = f_bfree - f_bresvd; 183.Ed 184.El 185.Sh SEE ALSO 186.Xr statvfs 2 187.Sh HISTORY 188The 189.In sys/statvfs.h 190header first appeared in 191.Nx 3.0 . 192