1.\" Copyright (c) 1995 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 4. Neither the name of the University nor the names of its contributors 13.\" may be used to endorse or promote products derived from this software 14.\" without specific prior written permission. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.\" @(#)kvm_getvfsbyname.3 8.3 (Berkeley) 5/4/95 29.\" $FreeBSD$ 30.\" 31.Dd April 5, 2007 32.Dt GETVFSBYNAME 3 33.Os 34.Sh NAME 35.Nm getvfsbyname 36.Nd get information about a file system 37.Sh LIBRARY 38.Lb libc 39.Sh SYNOPSIS 40.In sys/param.h 41.In sys/mount.h 42.Ft int 43.Fn getvfsbyname "const char *name" "struct xvfsconf *vfc" 44.Sh DESCRIPTION 45The 46.Fn getvfsbyname 47function provides access to information about a 48file system module that is configured in the kernel. 49If successful, 50the requested file system 51.Fa xvfsconf 52is returned in the location pointed to by 53.Fa vfc . 54The fields in a 55.Dq Li struct xvfsconf 56are defined as follows: 57.Pp 58.Bl -tag -compact -width vfc_refcount 59.It vfc_name 60the name of the file system 61.It vfc_typenum 62the file system type number assigned by the kernel 63.It vfc_refcount 64the number of active mount points using the file system 65.It vfc_flags 66flag bits, as described below 67.El 68.Pp 69The flags are defined as follows: 70.Pp 71.Bl -tag -width VFCF_DELEGADMIN -compact 72.It Dv VFCF_STATIC 73statically compiled into kernel 74.It Dv VFCF_NETWORK 75may get data over the network 76.It Dv VFCF_READONLY 77writes are not implemented 78.It Dv VFCF_SYNTHETIC 79data does not represent real files 80.It Dv VFCF_LOOPBACK 81aliases some other mounted FS 82.It Dv VFCF_UNICODE 83stores file names as Unicode 84.It Dv VFCF_JAIL 85can be mounted from within a jail if 86.Va security.jail.mount_allowed 87sysctl is set to 88.Dv 1 89.It Dv VFCF_DELEGADMIN 90supports delegated administration if 91.Va vfs.usermount 92sysctl is set to 93.Dv 1 94.El 95.Sh RETURN VALUES 96.Rv -std getvfsbyname 97.Sh ERRORS 98The following errors may be reported: 99.Bl -tag -width Er 100.It Bq Er EFAULT 101The 102.Fa vfc 103argument 104points to an invalid address. 105.It Bq Er ENOENT 106The 107.Fa name 108argument 109specifies a file system that is unknown or not configured in the kernel. 110.El 111.Sh SEE ALSO 112.Xr jail 2 , 113.Xr mount 2 , 114.Xr sysctl 3 , 115.Xr jail 8 , 116.Xr mount 8 , 117.Xr sysctl 8 118.Sh HISTORY 119A variant of the 120.Fn getvfsbyname 121function first appeared in 122.Fx 2.0 . 123