posix31.htm
来自「ST20 Embedded Toolset R2.0.5用于开发基于ST20芯片」· HTM 代码 · 共 153 行
HTM
153 行
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<meta name="GENERATOR" content="Quadralay WebWorks Publisher Professional Edition 6.0.5">
<meta name="TEMPLATEBASE" content="book_html">
<meta name="LASTUPDATED" content="12/04/03 16:07:18">
<title>device_unregister_desc</title>
<STYLE TYPE="text/css">
<!--
span.Signal { text-transform: uppercase; font-family: Verdana }
-->
</STYLE>
</head>
<body link="#3366CC" vlink="#9999CC" text="#000000" alink="#0000CC" bgcolor="#FFFFFF"
background="images/backgrnd.gif">
<p><img src="images/stlogo.gif" width="106" height="83" align="left"
alt="logo here!"> </p>
<table width="331" border="0" align="right" cellpadding="0" cellspacing="0">
<tr>
<td><a href="a_refman.htm"><img src="images/navtoc.gif" width="84" height="23"
border="0" alt="TOC"> </a></td>
<td><a href="posix30.htm"><img src="images/navprev.gif" width="80" height="23"
border="0" alt="PREV"> </a></td>
<td><a href="libsrcu.htm"><img src="images/navnext.gif" width="83" height="23"
border="0" alt="NEXT"> </a></td>
<td><a href="a_refmaa.htm"><img src="images/navidx.gif" width="84" height="23"
border="0" alt="INDEX"> </a></td>
</tr>
</table>
<p><br clear="all">
</p>
<hr align="left">
<blockquote>
<h2>
<a name="1205062"> </a><font color="#003366" face="Verdana, Arial, Helvetica, sans-serif">device_unregister_desc</font>
</h2><hr>
<p>
<a name="1205063"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">Unregister a device</font>
</p>
<h3>
<a name="1205064"> </a><font color="#003366" face="Verdana, Arial, Helvetica, sans-serif">Synopsis</font>
</h3>
<a name="1205065"> </a><font size=2 face=Courier><strong>#include <dev.h><br></strong></font>
<a name="1205066"> </a><font size=2 face=Courier><strong>int device_unregister( dev_desc_t* <font size=2 face=Courier><strong><em>desc </em></strong></font>);<br></strong></font>
<h3>
<a name="1205067"> </a><font color="#003366" face="Verdana, Arial, Helvetica, sans-serif">Arguments</font>
</h3>
<p>
<a name="1207876"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif"><b><font size=2 face=Courier><strong>dev_desc_t* </strong></font><font size=2 face=Courier><strong><em>desc</em></strong></font></b></font>
<br>
<dl><dl> <dl>
<dt> <a name="1207878"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">A pointer to a device descriptor</font>
</dl>
</dl></dl>
<h3>
<a name="1205070"> </a><font color="#003366" face="Verdana, Arial, Helvetica, sans-serif">Results</font>
</h3>
<p>
<a name="1205071"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">Returns <font size=2 face=Courier><strong>0</strong></font> on success, or <font size=2 face=Courier><strong>-1</strong></font> if an error occurs.</font>
</p>
<h3>
<a name="1205072"> </a><font color="#003366" face="Verdana, Arial, Helvetica, sans-serif">Errors</font>
</h3>
<p>
<a name="1205073"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">Returns <font size=2 face=Courier><strong>-1</strong></font> if <font size=2 face=Courier><strong>ops</strong></font> is <font size=2 face=Courier><strong>NULL</strong></font> or <font size=2 face=Courier><strong>desc</strong></font> is not a registered device lookup table.</font>
</p>
<h3>
<a name="1205074"> </a><font color="#003366" face="Verdana, Arial, Helvetica, sans-serif">Description</font>
</h3>
<p>
<a name="1205075"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif"><font size=2 face=Courier><strong>device_unregister_desc()</strong></font> attempts to unregister a device previously registered using <font size=2 face=Courier><strong>device_register()</strong></font> or <font size=2 face=Courier><strong>device_register_init()</strong></font>. This involves searching the device list for the appropriate device.</font>
</p>
<p>
<a name="1205076"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif"><font size=2 face=Courier><strong>device_unregister_desc()</strong></font> checks the file descriptor table for files which are currently open and associated with the device being unregistered. Any such files are marked as having no associated device, thus causing further I/O operations on those files to fail.</font>
</p>
<h3>
<a name="1205077"> </a><font color="#003366" face="Verdana, Arial, Helvetica, sans-serif">Example</font>
</h3>
<a name="1205078"> </a><font size=2 face=Courier><strong>extern dev_op_t asc_ops;<br>dev_desc_t* desc = device_register("asc", 0, &asc_ops);<br><font size=2 face=Courier><em>...</em></font> <br>device_unregister_desc(desc);<br></strong></font>
<h3>
<a name="1205082"> </a><font color="#003366" face="Verdana, Arial, Helvetica, sans-serif">See also</font>
</h3>
<p>
<a name="1205083"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif"><a href="posix27.htm#1204947"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>device_register</i></font></a>, <a href="posix28.htm#1204981"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>device_register_init</i></font></a>, <a href="posix30.htm#1205039"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>device_unregister</i></font></a></font>
</p>
</blockquote>
<hr>
<table width="331" border="0" align="left" cellpadding="0" cellspacing="0">
<tr>
<td><a href="a_refman.htm"><img src="images/navtoc.gif" width="84" height="23"
border="0" alt="TOC"> </a></td>
<td><a href="posix30.htm"><img src="images/navprev.gif" width="80" height="23"
border="0" alt="PREV"> </a></td>
<td><a href="libsrcu.htm"><img src="images/navnext.gif" width="83" height="23"
border="0" alt="NEXT"> </a></td>
<td><a href="a_refmaa.htm"><img src="images/navidx.gif" width="84" height="23"
border="0" alt="INDEX"> </a></td>
</tr>
</table>
<font size=1 face="Verdana, Arial, Helvetica, sans-serif"> © 2001, 2002, 2003 STMicroelectronics. All Rights Reserved.<br>
ADCS 7250966F</font>
</body>
</html>
⌨️ 快捷键说明
复制代码Ctrl + C
搜索代码Ctrl + F
全屏模式F11
增大字号Ctrl + =
减小字号Ctrl + -
显示快捷键?