xref: /openbsd/share/man/man9/vhold.9 (revision e5dd7070)
1.\"     $OpenBSD: vhold.9,v 1.9 2013/07/17 20:21:55 schwarze Exp $
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3.\" Copyright (C) 2001 Chad David <davidc@acns.ab.ca>. All rights reserved.
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28.\" $FreeBSD: src/share/man/man9/vhold.9,v 1.2 2001/12/14 09:11:13 ru Exp $
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30.Dd $Mdocdate: July 17 2013 $
31.Dt VHOLD 9
32.Os
33.Sh NAME
34.Nm vhold ,
35.Nm vdrop
36.Nd acquire/release a hold on a vnode
37.Sh SYNOPSIS
38.In sys/param.h
39.In sys/vnode.h
40.Ft void
41.Fn vhold "struct vnode *vp"
42.Ft void
43.Fn vdrop "struct vnode *vp"
44.Sh DESCRIPTION
45The
46.Fn vhold
47function increments the
48.Va v_holdcnt
49of the given vnode.
50If the vnode has already been added to the free list and its
51.Va v_holdcnt
52and
53.Va v_usecount
54are both zero, it will be removed from the free list and
55added to the vnode hold list.
56.Pp
57The
58.Fn vdrop
59function decrements the
60.Va v_holdcnt
61of the given vnode.
62If the vnode is on the vnode hold list and its
63.Va v_holdcnt
64and
65.Va v_usecount
66are both zero, it will be removed from the vnode hold list and
67added to the freed list.
68.Sh SEE ALSO
69.Xr vnode 9
70.Sh AUTHORS
71This man page was originally written by
72.An Chad David Aq Mt davidc@acns.ab.ca
73for
74.Fx .
75