173 lines
6.0 KiB
HTML
173 lines
6.0 KiB
HTML
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
|
|
<html>
|
|
<head>
|
|
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
|
|
<meta name="Copyright" content="Copyright (c) 2006 by IBM Corporation">
|
|
<title>pthread_mutexattr_setname_np()--Set Name in Mutex Attributes Object</title>
|
|
<!-- All rights reserved. Licensed Materials Property of IBM -->
|
|
<!-- US Government Users Restricted Rights -->
|
|
<!-- Use, duplication or disclosure restricted by -->
|
|
<!-- GSA ADP Schedule Contract with IBM Corp. -->
|
|
<!-- Begin Header Records ========================================== -->
|
|
<!-- NETMG2 SCRIPT A converted by B2H R4.1 (346) (CMS) by HOLTJM at -->
|
|
<!-- RCHVMW2 on 29 Jan 1999 at 10:01:37 -->
|
|
<!--File Edited November 2001 -->
|
|
<!--End Header Records -->
|
|
<link rel="stylesheet" type="text/css" href="../rzahg/ic.css">
|
|
</head>
|
|
<body>
|
|
|
|
<!-- Java sync-link -->
|
|
<script language="Javascript" src="../rzahg/synch.js" type="text/javascript">
|
|
</script>
|
|
|
|
<a name="Top_Of_Page"></a>
|
|
|
|
<h2>pthread_mutexattr_setname_np()--Set Name in Mutex Attributes Object</h2>
|
|
|
|
<div class="box" style="width: 80%;">
|
|
<br>
|
|
Syntax:
|
|
<pre> #include <pthread.h>
|
|
int pthread_mutexattr_setname_np(pthread_mutexattr_t *attr, const char *name); </pre>
|
|
Service Program Name: QP0WPTHR<br>
|
|
<!-- iddvc RMBR -->
|
|
<br>
|
|
Default Public Authority: *USE <br>
|
|
<!-- iddvc RMBR -->
|
|
<br>
|
|
Threadsafe: Yes<br>
|
|
<!-- iddvc RMBR -->
|
|
<br>
|
|
Signal Safe: Yes<br>
|
|
<!-- iddvc RMBR -->
|
|
<br>
|
|
</div>
|
|
|
|
<p>The <strong>pthread_mutexattr_setname_np</strong>() function changes the name attribute associated with the mutex attribute specified by <em>attr</em>. The buffer specified by <em>name</em> must contain a null terminated string of 15 characters or less in length (not including the NULL). If the length of name is greater than 15 characters, the excess characters are ignored. If <em>name</em> is null, the mutex name attribute is reset to the default.</p>
|
|
|
|
<p>By default, each pthread_mutex_t has the name "QP0WMTX UNNAMED" associated with it. The name attribute is used by various i5/OS system utilities to aid in debug and service. One example is the WRKJOB command, which has a `work with mutexes' menu choice to show which mutexes are currently locked and which mutexes are being waited for.</p>
|
|
|
|
<p>If you should give unique names to all mutexes created to aid in debugging deadlock or performance problems. Use the CL command <strong>WRKJOB</strong>, option 20, to help debug mutex deadlocks.</p>
|
|
|
|
<p><strong>Note:</strong> This function is not portable.</p>
|
|
|
|
<br>
|
|
<h3>Authorities and Locks</h3>
|
|
|
|
<p>None.</p>
|
|
|
|
<br>
|
|
<h3>Parameters</h3>
|
|
|
|
<dl>
|
|
<dt><strong>attr</strong></dt>
|
|
|
|
<dd>(Input) Address of the mutex attributes object</dd>
|
|
|
|
<dt><strong>name</strong></dt>
|
|
|
|
<dd>(Input) Address of a null terminated character buffer containing the name</dd>
|
|
</dl>
|
|
|
|
<br>
|
|
<h3>Return Value</h3>
|
|
|
|
<dl>
|
|
<dt><strong>0</strong></dt>
|
|
|
|
<dd><strong>pthread_mutexattr_setname_np</strong>() was successful.</dd>
|
|
|
|
<dt><strong>value</strong></dt>
|
|
|
|
<dd><strong>pthread_mutexattr_setname_np</strong>() was not successful. <em>value</em> is set to indicate the error condition.</dd>
|
|
</dl>
|
|
|
|
<br>
|
|
<h3>Error Conditions</h3>
|
|
|
|
<p>If <strong>pthread_mutexattr_setname_np</strong>() was not successful, the error condition returned usually indicates one of the following errors. Under some conditions, the value returned could indicate an error other than those listed here.</p>
|
|
|
|
<dl>
|
|
<dt><em>[EINVAL]</em></dt>
|
|
|
|
<dd><p>The value specified for the argument is not correct.</p></dd>
|
|
</dl>
|
|
|
|
<br>
|
|
<h3>Related Information</h3>
|
|
|
|
<ul>
|
|
<li>The <<strong>pthread.h</strong>> header file. See <a href="rzah4hed.htm">Header files for Pthread functions</a>.<br><br></li>
|
|
|
|
<li><a href="users_51.htm">pthread_mutexattr_getname_np()</a>--Get Name from Mutex Attributes Object<br><br></li>
|
|
|
|
<li><a href="users_61.htm">pthread_mutex_initdone()</a>--Initialize Mutex</li>
|
|
</ul>
|
|
|
|
<br>
|
|
<h3>Example</h3>
|
|
<p>See <a href="../apiref/aboutapis.htm#codedisclaimer">Code disclaimer information</a>
|
|
for information pertaining to code examples.</p>
|
|
<pre>#include <pthread.h>
|
|
#include <stdio.h>
|
|
#include "check.h"
|
|
|
|
int main(int argc, char **argv)
|
|
{
|
|
int rc=0;
|
|
pthread_mutexattr_t mta;
|
|
char mutexname[16];
|
|
|
|
printf("Entering testcase\n");
|
|
|
|
printf("Create a default mutex attribute\n");
|
|
rc = pthread_mutexattr_init(&mta);
|
|
checkResults("pthread_mutexattr_init\n", rc);
|
|
|
|
memset(mutexname, 0, sizeof(mutexname));
|
|
printf("Find out what the default name of the mutex is\n");
|
|
rc = pthread_mutexattr_getname_np(&mta, mutexname);
|
|
checkResults("pthread_mutexattr_getname_np()\n", rc);
|
|
|
|
printf("The default mutex name will be: %.15s\n", mutexname);
|
|
printf("- At this point, mutexes created with this attribute\n");
|
|
printf("- will show up by name on many i5/OS debug and service screens\n");
|
|
printf("- The default attribute contains a special automatically\n");
|
|
printf("- incrementing name that changes for each mutex created in \n");
|
|
printf("- the process\n");
|
|
|
|
printf("Destroy mutex attribute\n");
|
|
rc = pthread_mutexattr_destroy(&mta);
|
|
checkResults("pthread_mutexattr_destroy()\n", rc);
|
|
|
|
printf("Main completed\n");
|
|
return 0;
|
|
}</pre>
|
|
|
|
<p><strong>Output:</strong></p>
|
|
|
|
<pre>Entering testcase
|
|
Create a default mutex attribute
|
|
Find out what the default name of the mutex is
|
|
The default mutex name will be: QP0WMTX UNNAMED
|
|
The new mutex name will be: <My Mutex>
|
|
Destroy mutex attribute
|
|
Main completed</pre>
|
|
|
|
<hr>
|
|
API introduced: V4R3
|
|
<hr>
|
|
<center>
|
|
<table cellpadding="2" cellspacing="2">
|
|
<tr align="center">
|
|
<td valign="middle" align="center"><a href="#Top_Of_Page">Top</a> |
|
|
<a href="rzah4mst.htm">Pthread APIs</a> |
|
|
<a href="aplist.htm">APIs by category</a></td>
|
|
</tr>
|
|
</table>
|
|
</center>
|
|
|
|
</body>
|
|
</html>
|