.\"     $OpenBSD: vhold.9,v 1.9 2013/07/17 20:21:55 schwarze Exp $
.\"
.\" Copyright (C) 2001 Chad David <davidc@acns.ab.ca>. All rights reserved.
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.\" $FreeBSD: src/share/man/man9/vhold.9,v 1.2 2001/12/14 09:11:13 ru Exp $
.\"
.Dd $Mdocdate: July 17 2013 $
.Dt VHOLD 9
.Os
.Sh NAME
.Nm vhold ,
.Nm vdrop
.Nd acquire/release a hold on a vnode
.Sh SYNOPSIS
.In sys/param.h
.In sys/vnode.h
.Ft void
.Fn vhold "struct vnode *vp"
.Ft void
.Fn vdrop "struct vnode *vp"
.Sh DESCRIPTION
The
.Fn vhold
function increments the
.Va v_holdcnt
of the given vnode.
If the vnode has already been added to the free list and its
.Va v_holdcnt
and
.Va v_usecount
are both zero, it will be removed from the free list and
added to the vnode hold list.
.Pp
The
.Fn vdrop
function decrements the
.Va v_holdcnt
of the given vnode.
If the vnode is on the vnode hold list and its
.Va v_holdcnt
and
.Va v_usecount
are both zero, it will be removed from the vnode hold list and
added to the freed list.
.Sh SEE ALSO
.Xr vnode 9
.Sh AUTHORS
This man page was originally written by
.An Chad David Aq Mt davidc@acns.ab.ca
for
.Fx .