Copyright (C) 2001 Chad David <davidc@acns.ab.ca>. All rights reserved.

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$FreeBSD$

.Dd April 1, 2007 .Dt VHOLD 9 .Os .Sh NAME .Nm vhold , vdrop , vdropl .Nd "acquire/release a hold on a vnode" .Sh SYNOPSIS n sys/param.h n sys/vnode.h .Ft void .Fn vhold "struct vnode *vp" .Ft void .Fn vholdl "struct vnode *vp" .Ft void .Fn vdrop "struct vnode *vp" .Ft void .Fn vdropl "struct vnode *vp" .Sh DESCRIPTION The .Fn vhold and .Fn vholdl functions increment 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.

p The .Fn vdrop and .Fn vdropl functions decrement the .Va v_holdcnt of the vnode. If the holdcount is less than or equal to zero prior to calling .Fn vdrop or .Fn vdropl , the system will panic. If the vnode is no longer referenced, it will be freed.

p .Fn vhold and .Fn vdrop lock the vnode interlock while .Fn vholdl and .Fn vdropl expect the interlock to already be held. .Sh SEE ALSO .Xr vnode 9 .Sh AUTHORS This manual page was written by .An Chad David Aq davidc@acns.ab.ca .