\section{\class{wxCondition}}\label{wxcondition}
-TODO
+wxCondition variables correspond to pthread conditions or to Win32 event
+objects. They may be used in a multithreaded application to wait until the
+given condition becomes true which happens when the condition becomes signaled.
+
+For example, if a worker thread is doing some long task and another thread has
+to wait until it is finished, the latter thread will wait on the condition
+object and the worker thread will signal it on exit (this example is not
+perfect because in this particular case it would be much better to just
+\helpref{Wait()}{wxthreadwait} for the worker thread, but if there are several
+worker threads it already makes much more sense).
+
+Note that a call to \helpref{Signal()}{wxconditionsignal} may happen before the
+other thread calls \helpref{Wait()}{wxconditionwait} and, just as with the
+pthread conditions, the signal is then lost and so if you want to be sure to
+get it you must use a mutex together with the condition variable.
+
+\wxheading{Example}
+
+This example shows how a main thread may launch a worker thread which starts
+running and then waits until the main thread signals it to continue:
+
+\begin{verbatim}
+class MyWaitingThread : public wxThread
+{
+public:
+ MyWaitingThread(wxMutex *mutex, wxCondition *condition)
+ {
+ m_mutex = mutex;
+ m_condition = condition;
+
+ Create();
+ }
+
+ virtual ExitCode Entry()
+ {
+ // wait for the signal from the main thread: it is absolutely necessary
+ // to look the mutex before doing it!
+ m_mutex->Lock();
+ m_condition->Signal();
+ m_mutex->Unlock();
+
+ ... do our job ...
+
+ return 0;
+ }
+
+private:
+ wxCondition *m_condition;
+};
+
+int main()
+{
+ wxMutex mutex;
+ wxCondition condition(mutex);
+
+ for ( int i = 0; i < 10; i++ )
+ {
+ MyWaitingThread *thread = new MyWaitingThread(&mutex, &condition);
+
+ thread->Run();
+ }
+
+ // wake up one of the threads
+ condition.Signal();
+
+ // wake up all the other ones
+ condition.Broadcast();
+
+ ... wait until they terminate or do something else ...
+
+ return 0;
+}
+\end{verbatim}
\wxheading{Derived from}
None.
+\wxheading{Include files}
+
+<wx/thread.h>
+
\wxheading{See also}
\helpref{wxThread}{wxthread}, \helpref{wxMutex}{wxmutex}
\membersection{wxCondition::wxCondition}\label{wxconditionconstr}
-\func{}{wxCondition}{\void}
+\func{}{wxCondition}{\param{wxMutex\& }{mutex}}
-Default constructor.
+Default and only constructor. The {\it mutex} must be locked by the caller
+before calling \helpref{Wait}{wxconditionwait} function.
\membersection{wxCondition::\destruct{wxCondition}}
\func{}{\destruct{wxCondition}}{\void}
-Destroys the wxCondition object.
+Destroys the wxCondition object. The destructor is not virtual so this class
+should not be used polymorphically.
\membersection{wxCondition::Broadcast}\label{wxconditionbroadcast}
\func{void}{Broadcast}{\void}
-Broadcasts to all waiting objects.
+Broadcasts to all waiting threads, waking all of them up. Note that this method
+may be called whether the mutex associated with this condition is locked or
+not.
+
+\wxheading{See also}
+
+\helpref{wxCondition::Signal}{wxconditionsignal}
\membersection{wxCondition::Signal}\label{wxconditionsignal}
\func{void}{Signal}{\void}
-Signals the object.
+Signals the object waking up at most one thread. If several threads are waiting
+on the same condition, the exact thread which is woken up is undefined. If no
+threads are waiting, the signal is lost and the condition would have to be
+signalled again to wake up any thread which may start waiting on it later.
+
+Note that this method may be called whether the mutex associated with this
+condition is locked or not.
+
+\wxheading{See also}
+
+\helpref{wxCondition::Broadcast}{wxconditionbroadcast}
\membersection{wxCondition::Wait}\label{wxconditionwait}
-\func{void}{Wait}{\param{wxMutex\&}{ mutex}}
+\func{void}{Wait}{\void}
-Waits indefinitely.
+Waits until the condition is signalled.
-\func{bool}{Wait}{\param{wxMutex\&}{ mutex}, \param{unsigned long}{ sec}, \param{unsigned long}{ nsec}}
+\func{bool}{Wait}{\param{unsigned long}{ sec}, \param{unsigned long}{ nsec}}
-Waits until a signal is raised or the timeout has elapsed.
+Waits until the condition is signalled or the timeout has elapsed.
-\wxheading{Parameters}
+Note that the mutex associated with this condition {\bf must} be acquired by
+the thread before calling this method.
-\docparam{mutex}{wxMutex object.}
+\wxheading{Parameters}
\docparam{sec}{Timeout in seconds}
\wxheading{Return value}
-The second form returns if the signal was raised, or FALSE if there was a timeout.
+The second form returns {\tt TRUE} if the condition has been signalled, or
+{\tt FALSE} if it returned because the timeout has elapsed.
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