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<a class="el" href="namespaceost.html">ost</a>::<a class="el" href="classost_1_1_conditional.html">Conditional</a></div>
<h1>ost::Conditional Class Reference</h1><!-- doxytag: class="ost::Conditional" -->A conditional variable synchcronization object for one to one and one to many signal and control events between processes.conditional.
<a href="#_details">More...</a>
<p>
<code>#include <<a class="el" href="thread_8h-source.html">thread.h</a>></code>
<p>
<p>Inheritance diagram for ost::Conditional:
<p><center><img src="classost_1_1_conditional.png" usemap="#ost::Conditional_map" border="0" alt=""></center>
<map name="ost::Conditional_map">
<area href="classost_1_1_buffer.html" alt="ost::Buffer" shape="rect" coords="0,56,100,80">
<area href="classost_1_1_fixed_buffer.html" alt="ost::FixedBuffer" shape="rect" coords="0,112,100,136">
</map>
<a href="classost_1_1_conditional-members.html">List of all members.</a><table border="0" cellpadding="0" cellspacing="0">
<tr><td></td></tr>
<tr><td colspan="2"><br><h2>Public Member Functions</h2></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top"> </td><td class="memItemRight" valign="bottom"><a class="el" href="classost_1_1_conditional.html#7d7009cab2b814c82b41d8682a6ebff0">Conditional</a> (const char *id=NULL)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Create an instance of a conditional. <a href="#7d7009cab2b814c82b41d8682a6ebff0"></a><br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top">virtual </td><td class="memItemRight" valign="bottom"><a class="el" href="classost_1_1_conditional.html#9772a4c8e522a010a37c63c5ee078384">~Conditional</a> ()</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Destroy the conditional. <a href="#9772a4c8e522a010a37c63c5ee078384"></a><br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top">void </td><td class="memItemRight" valign="bottom"><a class="el" href="classost_1_1_conditional.html#80822e8493bafb68bac637bbf5fe772d">signal</a> (bool broadcast)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Signal a conditional object and a waiting threads. <a href="#80822e8493bafb68bac637bbf5fe772d"></a><br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top">bool </td><td class="memItemRight" valign="bottom"><a class="el" href="classost_1_1_conditional.html#2cac07a385596391b0fc8c15b8a598e5">wait</a> (<a class="el" href="thread_8h.html#f412159e5cef839836a5e7b19ee75d1c">timeout_t</a> timer=0, bool locked=false)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Wait to be signaled from another thread. <a href="#2cac07a385596391b0fc8c15b8a598e5"></a><br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top">void </td><td class="memItemRight" valign="bottom"><a class="el" href="classost_1_1_conditional.html#e3fd225eeae79c24eb7f521f285e8289">enterMutex</a> (void)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Locks the conditional's mutex for this thread. <a href="#e3fd225eeae79c24eb7f521f285e8289"></a><br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top">void </td><td class="memItemRight" valign="bottom"><a class="el" href="classost_1_1_conditional.html#2a3bf89c582dad8ba7e81370fd361668">lock</a> (void)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">In the future we will use lock in place of enterMutex since the conditional composite is not a recursive mutex, and hence using enterMutex may cause confusion in expectation with the behavior of the <a class="el" href="classost_1_1_mutex.html">Mutex</a> class. <a href="#2a3bf89c582dad8ba7e81370fd361668"></a><br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top">bool </td><td class="memItemRight" valign="bottom"><a class="el" href="classost_1_1_conditional.html#dcd3f704ef27fff5501a42185a09471f">tryEnterMutex</a> (void)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Tries to lock the conditional for the current thread. <a href="#dcd3f704ef27fff5501a42185a09471f"></a><br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top">bool </td><td class="memItemRight" valign="bottom"><a class="el" href="classost_1_1_conditional.html#507839fac82a32f946fa5f87d41bef28">test</a> (void)</td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top">void </td><td class="memItemRight" valign="bottom"><a class="el" href="classost_1_1_conditional.html#cc29112f68c34a9844b3c3dad0d03603">leaveMutex</a> (void)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Leaving a mutex frees that mutex for use by another thread. <a href="#cc29112f68c34a9844b3c3dad0d03603"></a><br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top">void </td><td class="memItemRight" valign="bottom"><a class="el" href="classost_1_1_conditional.html#8b6126bbb6e58c1b8ef937bebf4af222">unlock</a> (void)</td></tr>
</table>
<hr><a name="_details"></a><h2>Detailed Description</h2>
A conditional variable synchcronization object for one to one and one to many signal and control events between processes.conditional.
<p>
<a class="el" href="classost_1_1_conditional.html">Conditional</a> variables may wait for and receive signals to notify when to resume or perform operations. Multiple waiting threads may be woken with a broadcast signal.<p>
<dl compact><dt><b>Warning:</b></dt><dd>While this class inherits from <a class="el" href="classost_1_1_mutex.html">Mutex</a>, the methods of the class <a class="el" href="classost_1_1_conditional.html">Conditional</a> just handle the system conditional variable, so the user is responsible for calling enterMutex and leaveMutex so as to avoid race conditions. Another thing to note is that if you have several threads waiting on one condition, not uncommon in thread pools, each thread must take care to manually unlock the mutex if cancellation occurs. Otherwise the first thread cancelled will deadlock the rest of the thread.</dd></dl>
<dl compact><dt><b>Author:</b></dt><dd>David Sugar </dd></dl>
<dl compact><dt><b><a class="el" href="todo.html#_todo000004">Todo:</a></b></dt><dd>implement in win32 </dd></dl>
<p>
<hr><h2>Constructor & Destructor Documentation</h2>
<a class="anchor" name="7d7009cab2b814c82b41d8682a6ebff0"></a><!-- doxytag: member="ost::Conditional::Conditional" ref="7d7009cab2b814c82b41d8682a6ebff0" args="(const char *id=NULL)" --><p>
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<td class="md" nowrap valign="top">ost::Conditional::Conditional </td>
<td class="md" valign="top">( </td>
<td class="md" nowrap valign="top">const char * </td>
<td class="mdname1" valign="top" nowrap> <em>id</em> = <code>NULL</code> </td>
<td class="md" valign="top"> ) </td>
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<p>
Create an instance of a conditional.
<p>
<dl compact><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>id</em> </td><td>name of conditional, optional for deadlock testing. </td></tr>
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</dl>
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<a class="anchor" name="9772a4c8e522a010a37c63c5ee078384"></a><!-- doxytag: member="ost::Conditional::~Conditional" ref="9772a4c8e522a010a37c63c5ee078384" args="()" --><p>
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<td class="md" nowrap valign="top">virtual ost::Conditional::~Conditional </td>
<td class="md" valign="top">( </td>
<td class="mdname1" valign="top" nowrap> </td>
<td class="md" valign="top"> ) </td>
<td class="md" nowrap><code> [virtual]</code></td>
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<p>
Destroy the conditional.
<p>
</td>
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<hr><h2>Member Function Documentation</h2>
<a class="anchor" name="e3fd225eeae79c24eb7f521f285e8289"></a><!-- doxytag: member="ost::Conditional::enterMutex" ref="e3fd225eeae79c24eb7f521f285e8289" args="(void)" --><p>
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<td class="md" nowrap valign="top">void ost::Conditional::enterMutex </td>
<td class="md" valign="top">( </td>
<td class="md" nowrap valign="top">void </td>
<td class="mdname1" valign="top" nowrap> </td>
<td class="md" valign="top"> ) </td>
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<p>
Locks the conditional's mutex for this thread.
<p>
Remember that Conditional's mutex is NOT a recursive mutex!<p>
<dl compact><dt><b>See also:</b></dt><dd><a class="el" href="classost_1_1_conditional.html#cc29112f68c34a9844b3c3dad0d03603">leaveMutex</a> </dd></dl>
</td>
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<a class="anchor" name="cc29112f68c34a9844b3c3dad0d03603"></a><!-- doxytag: member="ost::Conditional::leaveMutex" ref="cc29112f68c34a9844b3c3dad0d03603" args="(void)" --><p>
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<td class="md" nowrap valign="top">void ost::Conditional::leaveMutex </td>
<td class="md" valign="top">( </td>
<td class="md" nowrap valign="top">void </td>
<td class="mdname1" valign="top" nowrap> </td>
<td class="md" valign="top"> ) </td>
<td class="md" nowrap></td>
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<p>
Leaving a mutex frees that mutex for use by another thread.
<p>
<dl compact><dt><b>See also:</b></dt><dd><a class="el" href="classost_1_1_conditional.html#e3fd225eeae79c24eb7f521f285e8289">enterMutex</a> </dd></dl>
</td>
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<a class="anchor" name="2a3bf89c582dad8ba7e81370fd361668"></a><!-- doxytag: member="ost::Conditional::lock" ref="2a3bf89c582dad8ba7e81370fd361668" args="(void)" --><p>
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<td class="md" nowrap valign="top">void ost::Conditional::lock </td>
<td class="md" valign="top">( </td>
<td class="md" nowrap valign="top">void </td>
<td class="mdname1" valign="top" nowrap> </td>
<td class="md" valign="top"> ) </td>
<td class="md" nowrap><code> [inline]</code></td>
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<p>
In the future we will use lock in place of enterMutex since the conditional composite is not a recursive mutex, and hence using enterMutex may cause confusion in expectation with the behavior of the <a class="el" href="classost_1_1_mutex.html">Mutex</a> class.
<p>
<dl compact><dt><b>See also:</b></dt><dd><a class="el" href="classost_1_1_conditional.html#e3fd225eeae79c24eb7f521f285e8289">enterMutex</a> </dd></dl>
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<a class="anchor" name="80822e8493bafb68bac637bbf5fe772d"></a><!-- doxytag: member="ost::Conditional::signal" ref="80822e8493bafb68bac637bbf5fe772d" args="(bool broadcast)" --><p>
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<td class="md" nowrap valign="top">void ost::Conditional::signal </td>
<td class="md" valign="top">( </td>
<td class="md" nowrap valign="top">bool </td>
<td class="mdname1" valign="top" nowrap> <em>broadcast</em> </td>
<td class="md" valign="top"> ) </td>
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<p>
Signal a conditional object and a waiting threads.
<p>
<dl compact><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>broadcast</em> </td><td>this signal to all waiting threads if true. </td></tr>
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<a class="anchor" name="507839fac82a32f946fa5f87d41bef28"></a><!-- doxytag: member="ost::Conditional::test" ref="507839fac82a32f946fa5f87d41bef28" args="(void)" --><p>
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<td class="md" nowrap valign="top">bool ost::Conditional::test </td>
<td class="md" valign="top">( </td>
<td class="md" nowrap valign="top">void </td>
<td class="mdname1" valign="top" nowrap> </td>
<td class="md" valign="top"> ) </td>
<td class="md" nowrap><code> [inline]</code></td>
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<a class="anchor" name="dcd3f704ef27fff5501a42185a09471f"></a><!-- doxytag: member="ost::Conditional::tryEnterMutex" ref="dcd3f704ef27fff5501a42185a09471f" args="(void)" --><p>
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<td class="md" nowrap valign="top">bool ost::Conditional::tryEnterMutex </td>
<td class="md" valign="top">( </td>
<td class="md" nowrap valign="top">void </td>
<td class="mdname1" valign="top" nowrap> </td>
<td class="md" valign="top"> ) </td>
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<p>
Tries to lock the conditional for the current thread.
<p>
Behaves like <a class="el" href="classost_1_1_conditional.html#e3fd225eeae79c24eb7f521f285e8289">enterMutex</a> , except that it doesn't block the calling thread.<p>
<dl compact><dt><b>Returns:</b></dt><dd>true if locking the mutex was succesful otherwise false</dd></dl>
<dl compact><dt><b>See also:</b></dt><dd><a class="el" href="classost_1_1_conditional.html#e3fd225eeae79c24eb7f521f285e8289">enterMutex</a> <p>
<a class="el" href="classost_1_1_conditional.html#cc29112f68c34a9844b3c3dad0d03603">leaveMutex</a> </dd></dl>
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<a class="anchor" name="8b6126bbb6e58c1b8ef937bebf4af222"></a><!-- doxytag: member="ost::Conditional::unlock" ref="8b6126bbb6e58c1b8ef937bebf4af222" args="(void)" --><p>
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<td class="md" nowrap valign="top">void ost::Conditional::unlock </td>
<td class="md" valign="top">( </td>
<td class="md" nowrap valign="top">void </td>
<td class="mdname1" valign="top" nowrap> </td>
<td class="md" valign="top"> ) </td>
<td class="md" nowrap><code> [inline]</code></td>
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<a class="anchor" name="2cac07a385596391b0fc8c15b8a598e5"></a><!-- doxytag: member="ost::Conditional::wait" ref="2cac07a385596391b0fc8c15b8a598e5" args="(timeout_t timer=0, bool locked=false)" --><p>
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<td class="md" nowrap valign="top">bool ost::Conditional::wait </td>
<td class="md" valign="top">( </td>
<td class="md" nowrap valign="top"><a class="el" href="thread_8h.html#f412159e5cef839836a5e7b19ee75d1c">timeout_t</a> </td>
<td class="mdname" nowrap> <em>timer</em> = <code>0</code>, </td>
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<td class="md" nowrap align="right"></td>
<td class="md"></td>
<td class="md" nowrap>bool </td>
<td class="mdname" nowrap> <em>locked</em> = <code>false</code></td>
</tr>
<tr>
<td class="md"></td>
<td class="md">) </td>
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<p>
Wait to be signaled from another thread.
<p>
<dl compact><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>timer</em> </td><td>time period to wait. </td></tr>
<tr><td valign="top"></td><td valign="top"><em>locked</em> </td><td>flag if already locked the mutex. </td></tr>
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<hr>The documentation for this class was generated from the following file:<ul>
<li><a class="el" href="thread_8h-source.html">thread.h</a></ul>
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