freebsd-dev/share/man/man9/vhold.9

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.\"
.\" Copyright (C) 2001 Chad David <davidc@acns.ab.ca>. All rights reserved.
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.\" $FreeBSD$
.\"
.Dd November 21, 2001
.Dt VHOLD 9
.Os
.Sh NAME
.Nm vhold , 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 is still referenced,
it will be removed.
.Pp
The
.Fn vdrop
function decrements the
.Va v_holdcnt
of the vnode.
If the holdcount is less than or equal zero prior to calling
.Fn vdrop ,
the system will panic.
If the vnode is no longer referenced, it will freed.
.Sh SEE ALSO
.Xr vbusy 9 ,
.Xr vfree 9
.Sh AUTHORS
This man page was written by
.An Chad David Aq davidc@acns.ab.ca .