.\" Copyright (c) 1996 Doug Rabson
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.\" $FreeBSD: src/share/man/man9/vget.9,v 1.5.2.1 2001/12/17 11:30:19 ru Exp $
.\" $DragonFly: src/share/man/man9/vget.9,v 1.4 2004/06/01 11:36:53 hmp Exp $
.\"
.Dd July 24, 1996
.Os
.Dt VGET 9
.Sh NAME
.Nm vget
.Nd get a vnode from the free list
.Sh SYNOPSIS
.In sys/param.h
.In sys/vnode.h
.Ft int
.Fn vget "struct vnode *vp" "int lockflag" "struct proc *p"
.Sh DESCRIPTION
Get a vnode from the free list and increment its reference count.
.Bl -tag -width lockflag
.It Fa vp
the vnode to remove from the free list
.It Fa lockflag
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
.Xr vget 9
to increment the reference count and remove it from the free list.
.Sh SEE ALSO
.Xr vnode 9 ,
.Xr vput 9 ,
.Xr vref 9 ,
.Xr vrele 9
.Sh AUTHORS
This man page was written by
.An Doug Rabson .