1.\" $OpenBSD: statfs.2,v 1.29 2022/07/30 07:19:30 jsg Exp $ 2.\" $NetBSD: statfs.2,v 1.10 1995/06/29 11:40:48 cgd Exp $ 3.\" 4.\" Copyright (c) 1989, 1991, 1993 5.\" The Regents of the University of California. All rights reserved. 6.\" 7.\" Redistribution and use in source and binary forms, with or without 8.\" modification, are permitted provided that the following conditions 9.\" are met: 10.\" 1. Redistributions of source code must retain the above copyright 11.\" notice, this list of conditions and the following disclaimer. 12.\" 2. Redistributions in binary form must reproduce the above copyright 13.\" notice, this list of conditions and the following disclaimer in the 14.\" documentation and/or other materials provided with the distribution. 15.\" 3. Neither the name of the University nor the names of its contributors 16.\" may be used to endorse or promote products derived from this software 17.\" without specific prior written permission. 18.\" 19.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29.\" SUCH DAMAGE. 30.\" 31.\" @(#)statfs.2 8.3 (Berkeley) 2/11/94 32.\" 33.Dd $Mdocdate: July 30 2022 $ 34.Dt STATFS 2 35.Os 36.Sh NAME 37.Nm statfs , 38.Nm fstatfs 39.Nd get file system statistics 40.Sh SYNOPSIS 41.In sys/types.h 42.In sys/mount.h 43.Ft int 44.Fn statfs "const char *path" "struct statfs *buf" 45.Ft int 46.Fn fstatfs "int fd" "struct statfs *buf" 47.Sh DESCRIPTION 48.Fn statfs 49returns information about a mounted file system. 50.Fa path 51is the pathname of any file within the mounted file system. 52.Fa buf 53is a pointer to a 54.Nm statfs 55structure defined as follows: 56.Bd -literal 57typedef struct { int32_t val[2]; } fsid_t; 58 59#define MFSNAMELEN 16 /* length of fs type name, including nul */ 60#define MNAMELEN 90 /* length of buffer for returned name */ 61 62struct statfs { 63 u_int32_t f_flags; /* copy of mount flags */ 64 u_int32_t f_bsize; /* file system block size */ 65 u_int32_t f_iosize; /* optimal transfer block size */ 66 67 /* unit is f_bsize */ 68 u_int64_t f_blocks; /* total data blocks in file system */ 69 u_int64_t f_bfree; /* free blocks in fs */ 70 int64_t f_bavail; /* free blocks avail to non-superuser */ 71 72 u_int64_t f_files; /* total file nodes in file system */ 73 u_int64_t f_ffree; /* free file nodes in fs */ 74 int64_t f_favail; /* free file nodes avail to non-root */ 75 76 u_int64_t f_syncwrites; /* count of sync writes since mount */ 77 u_int64_t f_syncreads; /* count of sync reads since mount */ 78 u_int64_t f_asyncwrites; /* count of async writes since mount */ 79 u_int64_t f_asyncreads; /* count of async reads since mount */ 80 81 fsid_t f_fsid; /* file system id */ 82 u_int32_t f_namemax; /* maximum filename length */ 83 uid_t f_owner; /* user that mounted the file system */ 84 u_int64_t f_ctime; /* last mount [-u] time */ 85 86 char f_fstypename[MFSNAMELEN]; /* fs type name */ 87 char f_mntonname[MNAMELEN]; /* directory on which mounted */ 88 char f_mntfromname[MNAMELEN]; /* mounted file system */ 89 char f_mntfromspec[MNAMELEN]; /* special for mount request */ 90 union mount_info mount_info; /* per-filesystem mount options */ 91}; 92.Ed 93.Pp 94.Fn fstatfs 95returns the same information about an open file referenced by descriptor 96.Fa fd . 97.Pp 98Note that 99.Fa f_fsid 100will be empty unless the user is the superuser. 101.Sh RETURN VALUES 102.Rv -std 103.Sh ERRORS 104.Fn statfs 105fails if one or more of the following are true: 106.Bl -tag -width Er 107.It Bq Er ENOTDIR 108A component of the path prefix of 109.Fa path 110is not a directory. 111.It Bq Er ENAMETOOLONG 112A component of a pathname exceeded 113.Dv NAME_MAX 114characters, or an entire pathname (including the terminating NUL) 115exceeded 116.Dv PATH_MAX 117bytes. 118.It Bq Er ENOENT 119The file referred to by 120.Fa path 121does not exist. 122.It Bq Er EACCES 123Search permission is denied for a component of the path prefix of 124.Fa path . 125.It Bq Er ELOOP 126Too many symbolic links were encountered in translating 127.Fa path . 128.It Bq Er EFAULT 129.Fa buf 130or 131.Fa path 132points to an invalid address. 133.It Bq Er EIO 134An I/O error occurred while reading from or writing to the file system. 135.El 136.Pp 137.Fn fstatfs 138fails if one or more of the following are true: 139.Bl -tag -width Er 140.It Bq Er EBADF 141.Fa fd 142is not a valid open file descriptor. 143.It Bq Er EFAULT 144.Fa buf 145points to an invalid address. 146.It Bq Er EIO 147An I/O error occurred while reading from or writing to the file system. 148.El 149.Sh SEE ALSO 150.Xr df 1 , 151.Xr getfsstat 2 , 152.Xr mount 2 , 153.Xr stat 2 154.Sh HISTORY 155The 156.Fn statfs 157function first appeared in 158.Bx 4.3 Reno . 159