Mutexes may be recursive in the sense that a thread can lock a mutex which it
had already locked before (instead of dead locking the entire process in this
situation by starting to wait on a mutex which will never be released while the
-thread is waiting) but using them is not recommended and they are {\bf not}
-recursive by default. The reason for this is that recursive mutexes are not
-supported by all Unix flavours and, worse, they cannot be used with
-\helpref{wxCondition}{wxcondition}.
-
-For example, when several thread use the data stored in the linked list,
-modifications to the list should be only allowed to one thread at a time
+thread is waiting) but using them is not recommended under Unix and they are
+{\bf not} recursive there by default. The reason for this is that recursive
+mutexes are not supported by all Unix flavours and, worse, they cannot be used
+with \helpref{wxCondition}{wxcondition}. On the other hand, Win32 mutexes are
+always recursive.
+
+For example, when several threads use the data stored in the linked list,
+modifications to the list should only be allowed to one thread at a time
because during a new node addition the list integrity is temporarily broken
(this is also called {\it program invariant}).
s_mutexProtectingTheGlobalList->Unlock();
}
- // return true the given number is greater than all array elements
+ // return true if the given number is greater than all array elements
bool MyThread::IsGreater(int num)
{
// before using the list we must acquire the mutex
<wx/thread.h>
+\wxheading{Library}
+
+\helpref{wxBase}{librarieslist}
+
\wxheading{See also}
\helpref{wxThread}{wxthread}, \helpref{wxCondition}{wxcondition},
\latexignore{\rtfignore{\wxheading{Members}}}
+
\membersection{wxMutex::wxMutex}\label{wxmutexctor}
\func{}{wxMutex}{\param{wxMutexType }{type = {\tt wxMUTEX\_DEFAULT}}}
Default constructor.
+
\membersection{wxMutex::\destruct{wxMutex}}\label{wxmutexdtor}
\func{}{\destruct{wxMutex}}{\void}
Destroys the wxMutex object.
+
\membersection{wxMutex::Lock}\label{wxmutexlock}
\func{wxMutexError}{Lock}{\void}
-Locks the mutex object.
+Locks the mutex object. This is equivalent to
+\helpref{LockTimeout}{wxmutexlocktimeout} with infinite timeout.
\wxheading{Return value}
\begin{twocollist}\itemsep=0pt
\twocolitem{{\bf wxMUTEX\_NO\_ERROR}}{There was no error.}
\twocolitem{{\bf wxMUTEX\_DEAD\_LOCK}}{A deadlock situation was detected.}
-\twocolitem{{\bf wxMUTEX\_BUSY}}{The mutex is already locked by another thread.}
\end{twocollist}
+
+\membersection{wxMutex::LockTimeout}\label{wxmutexlocktimeout}
+
+\func{wxMutexError}{LockTimeout}{\param{unsigned long}{ msec}}
+
+Try to lock the mutex object during the specified time interval.
+
+\wxheading{Return value}
+
+One of:
+
+\twocolwidtha{7cm}
+\begin{twocollist}\itemsep=0pt
+\twocolitem{{\bf wxMUTEX\_NO\_ERROR}}{Mutex successfully locked.}
+\twocolitem{{\bf wxMUTEX\_TIMEOUT}}{Mutex couldn't be acquired before timeout expiration.}
+\twocolitem{{\bf wxMUTEX\_DEAD\_LOCK}}{A deadlock situation was detected.}
+\end{twocollist}
+
+
\membersection{wxMutex::TryLock}\label{wxmutextrylock}
\func{wxMutexError}{TryLock}{\void}
\twocolwidtha{7cm}
\begin{twocollist}\itemsep=0pt
\twocolitem{{\bf wxMUTEX\_NO\_ERROR}}{There was no error.}
-\twocolitem{{\bf wxMUTEX\_DEAD\_LOCK}}{A deadlock situation was detected.}
\twocolitem{{\bf wxMUTEX\_BUSY}}{The mutex is already locked by another thread.}
\end{twocollist}
+
\membersection{wxMutex::Unlock}\label{wxmutexunlock}
\func{wxMutexError}{Unlock}{\void}
\twocolwidtha{7cm}
\begin{twocollist}\itemsep=0pt
\twocolitem{{\bf wxMUTEX\_NO\_ERROR}}{There was no error.}
-\twocolitem{{\bf wxMUTEX\_DEAD\_LOCK}}{A deadlock situation was detected.}
-\twocolitem{{\bf wxMUTEX\_BUSY}}{The mutex is already locked by another thread.}
-\twocolitem{{\bf wxMUTEX\_UNLOCKED}}{The calling thread tries to unlock an unlocked mutex.}
+\twocolitem{{\bf wxMUTEX\_UNLOCKED}}{The calling thread doesn't own the mutex.}
\end{twocollist}