git.saurik.com Git - wxWidgets.git/blame_incremental

... / ...

Commit	Line	Data
	1	\section{\class{wxThread}}\label{wxthread}
	2
	3	A thread is basically a path of execution through a program. Threads are also
	4	sometimes called {\it light-weight processes}, but the fundamental difference
	5	between threads and processes is that memory spaces of different processes are
	6	separated while all threads share the same address space. While it makes it
	7	much easier to share common data between several threads, it also makes much
	8	easier to shoot oneself in the foot, so careful use of synchronization objects
	9	such as \helpref{mutexes}{wxmutex} and/or \helpref{critical sections}{wxcriticalsection} is recommended.
	10
	11	\wxheading{Derived from}
	12
	13	None.
	14
	15	\wxheading{Include files}
	16
	17	<wx/thread.h>
	18
	19	\wxheading{See also}
	20
	21	\helpref{wxMutex}{wxmutex}, \helpref{wxCondition}{wxcondition}, \helpref{wxCriticalSection}{wxcriticalsection}
	22
	23	\latexignore{\rtfignore{\wxheading{Members}}}
	24
	25	\membersection{wxThread::wxThread}\label{wxthreadctor}
	26
	27	\func{}{wxThread}{\void}
	28
	29	Default constructor: it doesn't create nor starts the thread.
	30
	31	\membersection{wxThread::\destruct{wxThread}}
	32
	33	\func{}{\destruct{wxThread}}{\void}
	34
	35	wxThread destructor is private, so you can not call it directly - i.e., deleting
	36	wxThread objects is forbidden. Instead, you should use \helpref{Delete}{wxthreaddelete} or
	37	\helpref{Kill}{wxthreadkill} methods. This also means that thread objects should
	38	eb {\bf always} allocated on the heap (i.e. with {\it new}) because the functions
	39	mentioned above will try to reclaim the storage from the heap.
	40
	41	\membersection{wxThread::Create}\label{wxthreadcreate}
	42
	43	\func{wxThreadError}{Create}{\void}
	44
	45	Creates a new thread. The thread object is created in the suspended state, you
	46	should call \helpref{Run}{wxthreadrun} to start running it.
	47
	48	\wxheading{Return value}
	49
	50	One of:
	51
	52	\twocolwidtha{7cm}
	53	\begin{twocollist}\itemsep=0pt
	54	\twocolitem{{\bf wxTHREAD\_NO\_ERROR}}{There was no error.}
	55	\twocolitem{{\bf wxTHREAD\_NO\_RESOURCE}}{There were insufficient resources to create a new thread.}
	56	\twocolitem{{\bf wxTHREAD\_RUNNING}}{The thread is already running.}
	57	\end{twocollist}
	58
	59	\membersection{wxThread::Delete}\label{wxthreaddelete}
	60
	61	\func{void}{Delete}{\void}
	62
	63	This function should be called to terminate this thread. Unlike \helpref{Kill}{wxthreadkill}, it
	64	gives the target thread the time to terminate gracefully. Because of this, however, this function
	65	may not return immediately and if the thread is "hung" won't return at all. Also, message processing
	66	is not stopped during this function execution, so the message handlers may be called from inside
	67	it.
	68
	69	Delete() may be called for thread in any state: running, paused or even not yet created. Moreover,
	70	it must be called if \helpref{Create}{wxthreadcreate} or \helpref{Run}{wxthreadrun} fail to free
	71	the memory occupied by the thread object.
	72
	73	\membersection{wxThread::Entry}\label{wxthreadentry}
	74
	75	\func{virtual void *}{Entry}{\void}
	76
	77	This is the entry point of the thread. This function is pure virtual and must
	78	be implemented by any derived class. The thread execution will start here.
	79
	80	The returned value is the thread exit code but is currently ignored in
	81	wxWindows implementation (this will change in near future).
	82
	83	\membersection{wxThread::GetID}\label{wxthreadgetid}
	84
	85	\constfunc{unsigned long}{GetID}{\void}
	86
	87	Gets the thread identifier: this is a platform dependent number which uniquely identifies the
	88	thread throughout the system during its existence (i.e. the thread identifiers may be reused).
	89
	90	\membersection{wxThread::GetPriority}\label{wxthreadgetpriority}
	91
	92	\constfunc{int}{GetPriority}{\void}
	93
	94	Gets the priority of the thread, between zero and 100.
	95
	96	The following priorities are already defined:
	97
	98	\twocolwidtha{7cm}
	99	\begin{twocollist}\itemsep=0pt
	100	\twocolitem{{\bf WXTHREAD\_MIN\_PRIORITY}}{0}
	101	\twocolitem{{\bf WXTHREAD\_DEFAULT\_PRIORITY}}{50}
	102	\twocolitem{{\bf WXTHREAD\_MAX\_PRIORITY}}{100}
	103	\end{twocollist}
	104
	105	\membersection{wxThread::IsAlive}\label{wxthreadisalive}
	106
	107	\constfunc{bool}{IsAlive}{\void}
	108
	109	Returns TRUE if the thread is alive (i.e. started and not terminating).
	110
	111	\membersection{wxThread::IsMain}\label{wxthreadismain}
	112
	113	\constfunc{bool}{IsMain}{\void}
	114
	115	Returns TRUE if the calling thread is the main application thread.
	116
	117	\membersection{wxThread::IsPaused}\label{wxthreadispaused}
	118
	119	\constfunc{bool}{IsPaused}{\void}
	120
	121	Returns TRUE if the thread is paused.
	122
	123	\membersection{wxThread::IsRunning}\label{wxthreadisrunning}
	124
	125	\constfunc{bool}{IsRunning}{\void}
	126
	127	Returns TRUE if the thread is running.
	128
	129	\membersection{wxThread::Kill}\label{wxthreadkill}
	130
	131	\func{wxThreadError}{Kill}{\void}
	132
	133	Immediately terminates the target thread. {\bf This function is dangerous and should
	134	be used with extreme care (and not used at all whenever possible)!} The resources
	135	allocated to the thread will not be freed and the state of the C runtime library
	136	may become inconsistent. Use \helpref{Delete()}{wxthreaddelete} instead.
	137
	138	\membersection{wxThread::OnExit}\label{wxthreadonexit}
	139
	140	\func{void}{OnExit}{\void}
	141
	142	Called when the thread exits. This function is called in the context of the thread
	143	associated with the wxThread object, not in the context of the main thread.
	144
	145	\membersection{wxThread::Run}\label{wxthreadrun}
	146
	147	\func{wxThreadError}{Run}{\void}
	148
	149	Runs the thread.
	150
	151	\membersection{wxThread::SetPriority}\label{wxthreadsetpriority}
	152
	153	\func{void}{SetPriority}{\param{int}{ priority}}
	154
	155	Sets the priority of the thread, between zero and 100. This must be set before the thread is created.
	156
	157	The following priorities are already defined:
	158
	159	\twocolwidtha{7cm}
	160	\begin{twocollist}\itemsep=0pt
	161	\twocolitem{{\bf WXTHREAD\_MIN\_PRIORITY}}{0}
	162	\twocolitem{{\bf WXTHREAD\_DEFAULT\_PRIORITY}}{50}
	163	\twocolitem{{\bf WXTHREAD\_MAX\_PRIORITY}}{100}
	164	\end{twocollist}
	165
	166	\membersection{wxThread::Sleep}\label{wxthreadsleep}
	167
	168	\func{\void}{Sleep}{\param{unsigned long }{milliseconds}}
	169
	170	Pauses the thread execution for the given amount of time.
	171
	172	This function should be used instead of \helpref{wxSleep}{wxsleep} by all worker
	173	(i.e. all except the main one) threads.
	174
	175	\membersection{wxThread::This}\label{wxthreadthis}
	176
	177	\func{wxThread *}{This}{\void}
	178
	179	Return the thread object for the calling thread. NULL is returned if the calling thread
	180	is the main (GUI) thread, but \helpref{IsMain}{wxthreadismain} should be used to test
	181	whether the thread is really the main one because NULL may also be returned for the thread
	182	not created with wxThread class. Generally speaking, the return value for such thread
	183	is undefined.
	184
	185	\membersection{wxThread::Yield}\label{wxthreadyield}
	186
	187	\func{\void}{Yield}{\void}
	188
	189	Give the rest of the thread time slice to the system allowing the other threads to run.
	190	See also \helpref{Sleep()}{wxthreadsleep}.
	191