.\"     $OpenBSD: vget.9,v 1.5 2003/06/06 20:56:32 jmc Exp $
.\" -*- nroff -*-
.\"
.\" Copyright (c) 1996 Doug Rabson
.\"
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.\" $FreeBSD: src/share/man/man9/vget.9,v 1.7 2001/12/26 23:14:04 davidc Exp $
.\"
.Dd July 24, 1996
.Os
.Dt VGET 9
.Sh NAME
.Nm vget
.Nd get a vnode from the free list
.Sh SYNOPSIS
.Fd #include <sys/param.h>
.Fd #include <sys/vnode.h>
.Ft int
.Fn vget "struct vnode *vp" "int flags" "struct proc *p"
.Sh DESCRIPTION
Get a vnode from the free list and increment its reference count.
.Bl -tag -width flags
.It Ar vp
the vnode to remove from the free list
.It Ar flags
if non-zero, the vnode will also be locked
.El
.Pp
When not in use, vnodes are kept on a free list.
The vnodes still
reference valid files but may be reused to refer to a new file at any
time.
Often, these vnodes are also held in caches in the system, such
as the name cache.
.Pp
When a vnode which is on the free list is used again, for instance if
the vnode was found in the name cache as a result of a call to
.Xr VOP_LOOKUP 9 ,
then the new user must call
.Fn vget
to increment the reference count and remove it from the free list.
.Sh ERRORS
.Bl -tag -width Er
.It Bq Er ENOENT
The vnode
.Fa vp
is in the process of being cleaned out from the underlying
file system.
.El
.Sh SEE ALSO
.Xr vnode 9 ,
.Xr vput 9 ,
.Xr vref 9 ,
.Xr vrele 9
.Sh AUTHORS
This man page was originally written by
.An Doug Rabson
for
.Fx .