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diff --git a/share/man/man9/vget.9 b/share/man/man9/vget.9 new file mode 100644 index 0000000..1a7d16c --- /dev/null +++ b/share/man/man9/vget.9 @@ -0,0 +1,71 @@ +.\" -*- nroff -*- +.\" +.\" Copyright (c) 1996 Doug Rabson +.\" +.\" All rights reserved. +.\" +.\" This program is free software. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY EXPRESS OR +.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES +.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. +.\" IN NO EVENT SHALL THE DEVELOPERS BE LIABLE FOR ANY DIRECT, INDIRECT, +.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT +.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF +.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +.\" +.\" $FreeBSD$ +.\" +.Dd July 24, 1996 +.Dt VGET 9 +.Os +.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 thread *td" +.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 +.Fn vget +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 manual page was written by +.An Doug Rabson . |