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diff --git a/src/stable/condition.h b/src/stable/condition.h
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+/*
+ * Copyright (C) 2007-2011 Xagasoft, All rights reserved.
+ *
+ * This file is part of the libbu++ library and is released under the
+ * terms of the license contained in the file LICENSE.
+ */
+
+#ifndef BU_CONDITION_H
+#define BU_CONDITION_H
+
+#include <pthread.h>
+
+#include "bu/mutex.h"
+
+namespace Bu
+{
+        /**
+         * Ito condition.  This is a fairly simple condition mechanism.  As you may
+         * notice this class inherits from the Mutex class, this is because all
+         * conditions must be within a locked block.  The standard usage of a
+         * condition is to pause one thread, perhaps indefinately, until another
+         * thread signals that it is alright to procede.
+         * <br>
+         * Standard usage for the thread that wants to wait is as follows:
+         * <pre>
+         * Condition cond;
+         * ... // Perform setup and enter your run loop
+         * cond.lock();
+         * while( !isFinished() ) // Could be anything you're waiting for
+         *     cond.wait();
+         * ...  // Take care of what you have to.
+         * cond.unlock();
+         * </pre>
+         * The usage for the triggering thread is much simpler, when it needs to
+         * tell the others that it's time to grab some data it calls either signal
+         * or broadcast.  See both of those functions for the difference.
+         *@ingroup Threading
+         */
+        class Condition : public Mutex
+        {
+        public:
+                /**
+                 * Create a condition.
+                 */
+                Condition();
+
+                /**
+                 * Destroy a condition.
+                 */
+                ~Condition();
+
+                /**
+                 * Wait forever, or until signalled.  This has to be called from within
+                 * a locked section, i.e. before calling this this object's lock
+                 * function should be called.
+                 */
+                int wait();
+
+                /**
+                 * Wait for a maximum of nSec seconds and nUSec micro-seconds or until
+                 * signalled.  This is a little more friendly function if you want to
+                 * perform other operations in the thrad loop that calls this function.
+                 * Like the other wait function, this must be inside a locked section.
+                 *@param nSec The seconds to wait.
+                 *@param nUSec the micro-seconds to wait.
+                 */
+                int wait( int nSec, int nUSec );
+
+                /**
+                 * Notify the next thread waiting on this condition that they can go
+                 * ahead.  This only signals one thread, the next one in the condition
+                 * queue, that it is safe to procede with whatever operation was being
+                 * waited on.
+                 */
+                int signal();
+
+                /**
+                 * Notify all threads waiting on this condition that they can go ahead
+                 * now. This function is slower than signal, but more effective in
+                 * certain situations where you may not know how many threads should be
+                 * activated.
+                 */
+                int broadcast();
+
+        private:
+                pthread_cond_t cond;    /**< Internal condition reference. */
+        };
+}
+
+#endif