<?xml version="1.0" encoding="UTF-8" standalone="no"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> <title>DbEnv::set_thread_id_string()</title> <link rel="stylesheet" href="apiReference.css" type="text/css" /> <meta name="generator" content="DocBook XSL Stylesheets V1.73.2" /> <link rel="start" href="index.html" title="Berkeley DB C++ API Reference" /> <link rel="up" href="env.html" title="Chapter 5. The DbEnv Handle" /> <link rel="prev" href="envset_thread_id.html" title="DbEnv::set_thread_id()" /> <link rel="next" href="envset_timeout.html" title="DbEnv::set_timeout()" /> </head> <body> <div class="navheader"> <table width="100%" summary="Navigation header"> <tr> <th colspan="3" align="center">DbEnv::set_thread_id_string()</th> </tr> <tr> <td width="20%" align="left"><a accesskey="p" href="envset_thread_id.html">Prev</a> </td> <th width="60%" align="center">Chapter 5. The DbEnv Handle </th> <td width="20%" align="right"> <a accesskey="n" href="envset_timeout.html">Next</a></td> </tr> </table> <hr /> </div> <div class="sect1" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h2 class="title" style="clear: both"><a id="envset_thread_id_string"></a>DbEnv::set_thread_id_string()</h2> </div> </div> </div> <pre class="programlisting">#include <db_cxx> int DbEnv::set_thread_id(void (*thread_id) (DbEnv *dbenv, pid_t *pid, db_threadid_t *tid)); </pre> <p> Declare a function that formats a process ID and thread ID identifier pair for display into a caller-supplied buffer. The function must return a reference to the caller-specified buffer. The <code class="methodname">DbEnv::set_thread_id_string()</code> method supports the <a class="xref" href="envset_thread_id.html" title="DbEnv::set_thread_id()">DbEnv::set_thread_id()</a> method. </p> <p> The <code class="methodname">DbEnv::set_thread_id_string()</code> method configures operations performed using the specified <a class="link" href="env.html" title="Chapter 5. The DbEnv Handle">DbEnv</a> handle, not all operations performed on the underlying database environment. </p> <p> The <code class="methodname">DbEnv::set_thread_id_string()</code> method may be called at any time during the life of the application. </p> <p> The <code class="methodname">DbEnv::set_thread_id_string()</code> <span> <span> method either returns a non-zero error value or throws an exception that encapsulates a non-zero error value on failure, and returns 0 on success. </span> </span> </p> <div class="sect2" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h3 class="title"><a id="id1675408"></a>Parameters</h3> </div> </div> </div> <div class="sect3" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h4 class="title"><a id="id1675413"></a>thread_id_string</h4> </div> </div> </div> <p> The <span class="bold"><strong>thread_id_string</strong></span> parameter is a function which returns a buffer in which is an identifier pair formatted for display. The function takes four arguments: </p> <div class="itemizedlist"> <ul type="disc"> <li> <p> <code class="literal">dbenv</code> </p> <p> The <span class="bold"><strong>dbenv</strong></span> parameter is the enclosing database environment handle, allowing application access to the application-private fields of that object. </p> </li> <li> <p> <code class="literal">pid</code> </p> <p> The <span class="bold"><strong>pid</strong></span> argument is a process ID. </p> </li> <li> <p> <code class="literal">tid</code> </p> <p> The <span class="bold"><strong>tid</strong></span> argument is a thread ID. </p> </li> <li> <p> <code class="literal">buf</code> </p> <p> The <span class="bold"><strong>buf</strong></span> argument is character array of at least DB_THREADID_STRLEN bytes in length, into which the identifier pair should be formatted. </p> </li> </ul> </div> <p> If no <span class="bold"><strong>thread_id_string</strong></span> function is specified, the default routine displays the identifier pair as "pid/tid", that is, the process ID represented as an unsigned integer value, a slash ('/') character, then the thread ID represented as an unsigned integer value. </p> </div> </div> <div class="sect2" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h3 class="title"><a id="id1675695"></a>Errors</h3> </div> </div> </div> <p> The <code class="methodname">DbEnv::set_thread_id_string()</code> <span> <span> method may fail and throw a <a class="link" href="dbexception.html" title="Chapter 6. The DbException Class">DbException</a> exception, encapsulating one of the following non-zero errors, or return one of the following non-zero errors: </span> </span> </p> <div class="sect3" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h4 class="title"><a id="id1675617"></a>EINVAL</h4> </div> </div> </div> <p> An invalid flag value or parameter was specified. </p> </div> </div> <div class="sect2" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h3 class="title"><a id="id1675659"></a>Class</h3> </div> </div> </div> <p> <a class="link" href="env.html" title="Chapter 5. The DbEnv Handle">DbEnv</a> </p> </div> <div class="sect2" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h3 class="title"><a id="id1675429"></a>See Also</h3> </div> </div> </div> <p> <a class="xref" href="env.html#envlist" title="Database Environments and Related Methods">Database Environments and Related Methods</a> </p> </div> </div> <div class="navfooter"> <hr /> <table width="100%" summary="Navigation footer"> <tr> <td width="40%" align="left"><a accesskey="p" href="envset_thread_id.html">Prev</a> </td> <td width="20%" align="center"> <a accesskey="u" href="env.html">Up</a> </td> <td width="40%" align="right"> <a accesskey="n" href="envset_timeout.html">Next</a></td> </tr> <tr> <td width="40%" align="left" valign="top">DbEnv::set_thread_id() </td> <td width="20%" align="center"> <a accesskey="h" href="index.html">Home</a> </td> <td width="40%" align="right" valign="top"> DbEnv::set_timeout()</td> </tr> </table> </div> </body> </html>