libdb/docs/api_reference/CXX/dblocknotgranted.html

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<h2 class="title" style="clear: both"><a id="dblocknotgranted"></a>DbLockNotGrantedException</h2>
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<pre class="programlisting">#include &lt;db_cxx.h&gt;
class DbLockNotGrantedException : public DbException {
public:
db_lockop_t get_op() const;
db_lockmode_t get_mode() const;
const Dbt* get_obj() const;
DbLock *get_lock() const;
int get_index() const;
}; </pre>
<p>
This information describes the <code class="classname">DbLockNotGrantedException</code> class and how
it is used by the various Berkeley DB classes.
</p>
<p>
A <code class="classname">DbLockNotGrantedException</code> is thrown when
lock or transaction timeouts have been configured, a database operation has timed out, and the
<a class="link" href="envset_flags.html#envset_flags_DB_TIME_NOTGRANTED">DB_TIME_NOTGRANTED</a>
configuration flag has been specified.
</p>
<p>
Additionally <code class="classname">DbLockNotGrantedException</code> is thrown when a Berkeley DB
Concurrent Data Store database environment configured for lock timeouts was unable to grant
a lock in the allowed time.
</p>
<p>
Finally, <code class="classname">DbLockNotGrantedException</code> is thrown when a lock requested using the
<a class="xref" href="lockget.html" title="DbEnv::lock_get()">DbEnv::lock_get()</a>
or
<a class="xref" href="lockvec.html" title="DbEnv::lock_vec()">DbEnv::lock_vec()</a>
methods, where the <a class="link" href="lockvec.html#vec_DB_LOCK_NOWAIT">DB_LOCK_NOWAIT</a>
flag or lock timers were configured, could not be granted before the wait-time expired.
</p>
<p>
The <a class="link" href="dbexception.html" title="Chapter 6. The DbException Class">DbException</a> errno value is set to
<code class="literal">DB_LOCK_NOTGRANTED</code>.
</p>
<p>
The following getter methods are available on this class:
</p>
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<p>
<code class="methodname">get_op()</code>
</p>
<p>
Returns <code class="literal">DB_LOCK_GET</code> when <a class="xref" href="lockget.html" title="DbEnv::lock_get()">DbEnv::lock_get()</a>
was called, and returns the <span class="bold"><strong>op</strong></span> for the failed
<code class="literal">DB_LOCKREQ</code> when <a class="xref" href="lockvec.html" title="DbEnv::lock_vec()">DbEnv::lock_vec()</a>
was called. If this exception is raised due to a database
operation, <code class="literal">DB_LOCK_GET</code> is returned.
</p>
</li>
<li>
<p>
<code class="methodname">get_mode()</code>
</p>
<p>
Returns the <span class="bold"><strong>mode</strong></span> parameter when
<a class="xref" href="lockget.html" title="DbEnv::lock_get()">DbEnv::lock_get()</a> was called, and returns the
<span class="bold"><strong>mode</strong></span> for the failed <code class="literal">DB_LOCKREQ</code>
when <a class="xref" href="lockvec.html" title="DbEnv::lock_vec()">DbEnv::lock_vec()</a> was called.
If this exception is raised due to a database operation,
<code class="literal">DB_LOCK_NG</code> is returned.
</p>
</li>
<li>
<p>
<code class="methodname">get_obj()</code>
</p>
<p>
Returns the <span class="bold"><strong>object</strong></span> parameter when
<a class="xref" href="lockget.html" title="DbEnv::lock_get()">DbEnv::lock_get()</a> was called, and returns the
<span class="bold"><strong>object</strong></span> for the failed <code class="literal">DB_LOCKREQ</code>
when <a class="xref" href="lockvec.html" title="DbEnv::lock_vec()">DbEnv::lock_vec()</a> was called.
The <a class="link" href="dbt.html" title="Chapter 4.  The Dbt Handle">Dbt</a> pointer may or may not refer valid
memory, depending on whether the <a class="link" href="dbt.html" title="Chapter 4.  The Dbt Handle">Dbt</a>
used in the call to the failed <a class="xref" href="lockget.html" title="DbEnv::lock_get()">DbEnv::lock_get()</a>
or <a class="xref" href="lockvec.html" title="DbEnv::lock_vec()">DbEnv::lock_vec()</a> method is still in
scope and has not been deleted.
</p>
</li>
<li>
<p>
<code class="methodname">get_lock()</code>
</p>
<p>
Returns NULL when <a class="xref" href="lockget.html" title="DbEnv::lock_get()">DbEnv::lock_get()</a> was called,
and returns the <span class="bold"><strong>lock</strong></span> in the failed <code class="literal">DB_LOCKREQ</code>
when <a class="xref" href="lockvec.html" title="DbEnv::lock_vec()">DbEnv::lock_vec()</a> was called.
If this exception is raised due to a database operation, NULL is returned.
</p>
</li>
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<p>
<code class="methodname">get_index()</code>
</p>
<p>
Returns <code class="literal">-1</code> when <a class="xref" href="lockget.html" title="DbEnv::lock_get()">DbEnv::lock_get()</a> was called,
and returns the index of the failed <code class="literal">DB_LOCKREQ</code>
when <a class="xref" href="lockvec.html" title="DbEnv::lock_vec()">DbEnv::lock_vec()</a> was called.
If this exception is raised due to a database operation,
<code class="literal">0</code> is returned.
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