freebsd-nq/lib/libc/gen/getvfsbyname.3
Warner Losh fbbd9655e5 Renumber copyright clause 4
Renumber cluase 4 to 3, per what everybody else did when BSD granted
them permission to remove clause 3. My insistance on keeping the same
numbering for legal reasons is too pedantic, so give up on that point.

Submitted by:	Jan Schaumann <jschauma@stevens.edu>
Pull Request:	https://github.com/freebsd/freebsd/pull/96
2017-02-28 23:42:47 +00:00

118 lines
3.4 KiB
Groff

.\" Copyright (c) 1995
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.\" @(#)kvm_getvfsbyname.3 8.3 (Berkeley) 5/4/95
.\" $FreeBSD$
.\"
.Dd August 30, 2016
.Dt GETVFSBYNAME 3
.Os
.Sh NAME
.Nm getvfsbyname
.Nd get information about a file system
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In sys/param.h
.In sys/mount.h
.Ft int
.Fn getvfsbyname "const char *name" "struct xvfsconf *vfc"
.Sh DESCRIPTION
The
.Fn getvfsbyname
function provides access to information about a
file system module that is configured in the kernel.
If successful,
the requested file system
.Fa xvfsconf
is returned in the location pointed to by
.Fa vfc .
The fields in a
.Dq Li struct xvfsconf
are defined as follows:
.Pp
.Bl -tag -compact -width vfc_refcount
.It vfc_name
the name of the file system
.It vfc_typenum
the file system type number assigned by the kernel
.It vfc_refcount
the number of active mount points using the file system
.It vfc_flags
flag bits, as described below
.El
.Pp
The flags are defined as follows:
.Pp
.Bl -tag -width VFCF_DELEGADMIN -compact
.It Dv VFCF_STATIC
statically compiled into kernel
.It Dv VFCF_NETWORK
may get data over the network
.It Dv VFCF_READONLY
writes are not implemented
.It Dv VFCF_SYNTHETIC
data does not represent real files
.It Dv VFCF_LOOPBACK
aliases some other mounted FS
.It Dv VFCF_UNICODE
stores file names as Unicode
.It Dv VFCF_JAIL
can be mounted from within a jail if
.Va security.jail.mount_allowed
sysctl is set to
.Dv 1
.It Dv VFCF_DELEGADMIN
supports delegated administration if
.Va vfs.usermount
sysctl is set to
.Dv 1
.El
.Sh RETURN VALUES
.Rv -std getvfsbyname
.Sh ERRORS
The following errors may be reported:
.Bl -tag -width Er
.It Bq Er ENOENT
The
.Fa name
argument
specifies a file system that is unknown or not configured in the kernel.
.El
.Sh SEE ALSO
.Xr jail 2 ,
.Xr mount 2 ,
.Xr sysctl 3 ,
.Xr jail 8 ,
.Xr mount 8 ,
.Xr sysctl 8
.Sh HISTORY
A variant of the
.Fn getvfsbyname
function first appeared in
.Fx 2.0 .