static/freebsd/man9/vget.9 4.html


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<table class="head">
  <tr>
    <td class="head-ltitle">VGET(9)</td>
    <td class="head-vol">Kernel Developer's Manual</td>
    <td class="head-rtitle">VGET(9)</td>
  </tr>
</table>
<div class="manual-text">
<section class="Sh">
<h1 class="Sh" id="NAME"><a class="permalink" href="#NAME">NAME</a></h1>
<p class="Pp"><code class="Nm">vget</code> &#x2014; <span class="Nd">get a vnode
    from the free list</span></p>
</section>
<section class="Sh">
<h1 class="Sh" id="SYNOPSIS"><a class="permalink" href="#SYNOPSIS">SYNOPSIS</a></h1>
<p class="Pp"><code class="In">#include
    &lt;<a class="In">sys/param.h</a>&gt;</code>
  <br/>
  <code class="In">#include &lt;<a class="In">sys/vnode.h</a>&gt;</code></p>
<p class="Pp"><var class="Ft">int</var>
  <br/>
  <code class="Fn">vget</code>(<var class="Fa" style="white-space: nowrap;">struct
    vnode *vp</var>, <var class="Fa" style="white-space: nowrap;">int
    lockflag</var>, <var class="Fa" style="white-space: nowrap;">struct thread
    *td</var>);</p>
</section>
<section class="Sh">
<h1 class="Sh" id="DESCRIPTION"><a class="permalink" href="#DESCRIPTION">DESCRIPTION</a></h1>
<p class="Pp">Get a vnode from the free list and increment its reference
  count.</p>
<dl class="Bl-tag">
  <dt><var class="Fa">vp</var></dt>
  <dd>The vnode to remove from the free list.</dd>
  <dt><var class="Fa">lockflag</var></dt>
  <dd>If non-zero, the vnode will also be locked.</dd>
</dl>
<p class="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.</p>
<p class="Pp" id="vget">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 <a class="Xr">VOP_LOOKUP(9)</a> then the new user must call
    <a class="permalink" href="#vget"><code class="Fn">vget</code></a>() to
    increment the reference count and remove it from the free list.</p>
</section>
<section class="Sh">
<h1 class="Sh" id="SEE_ALSO"><a class="permalink" href="#SEE_ALSO">SEE
  ALSO</a></h1>
<p class="Pp"><a class="Xr">vnode(9)</a>, <a class="Xr">vput(9)</a>,
    <a class="Xr">vref(9)</a>, <a class="Xr">vrele(9)</a></p>
</section>
<section class="Sh">
<h1 class="Sh" id="AUTHORS"><a class="permalink" href="#AUTHORS">AUTHORS</a></h1>
<p class="Pp">This manual page was written by <span class="An">Doug
    Rabson</span>.</p>
</section>
</div>
<table class="foot">
  <tr>
    <td class="foot-date">July 24, 1996</td>
    <td class="foot-os">FreeBSD 15.0</td>
  </tr>
</table>