Handles synchronous and a-synchronous timer events.

synchronous timer is registered into TSystem and is processed within the standard ROOT event-loop.
asynchronous timer is passed to the operating system which sends an external signal to ROOT and thus interrupts its event-loop.

You can use this class in one of the following ways:

Sub-class TTimer and override the Notify() method.
Re-implement the TObject::HandleTimer() method in your class and pass a pointer to this object to timer, see the SetObject() method.
Pass an interpreter command to timer, see SetCommand() method.
Create a TTimer, connect its Timeout() signal to the appropriate methods. Then when the time is up it will emit a Timeout() signal and call connected slots.

Minimum timeout interval is defined in TSystem::ESysConstants as kItimerResolution (currently 10 ms).

Signal/slots example:

TTimer *timer = new TTimer();
timer->Connect("Timeout()", "myObjectClassName",
               myObject, "TimerDone()");
timer->Start(2000, kTRUE);   // 2 seconds single-shot

To emit the Timeout signal repeatedly with minimum timeout:

timer->Start(0, kFALSE);

Definition at line 51 of file TTimer.h.

Public Member Functions
	TTimer (Long_t milliSec=0, Bool_t mode=kTRUE)
	Create timer that times out in ms milliseconds. More...

	TTimer (TObject *obj, Long_t milliSec, Bool_t mode=kTRUE)
	Create timer that times out in ms milliseconds. More...

	TTimer (const char *command, Long_t milliSec, Bool_t mode=kTRUE)
	Create timer that times out in ms milliseconds. More...

virtual	~TTimer ()

void	Add ()

Bool_t	CheckTimer (const TTime &now)
	Check if timer timed out. More...

TTime	GetAbsTime () const

const char *	GetCommand () const

TObject *	GetObject ()

TTime	GetTime () const

UInt_t	GetTimerID ()

Bool_t	HasTimedOut () const

Bool_t	IsAsync () const

Bool_t	IsInterruptingSyscalls () const

Bool_t	IsSync () const

virtual Bool_t	Notify ()
	Notify when timer times out. More...

void	Remove ()

void	Reset ()
	Reset the timer. More...

void	SetCommand (const char *command)
	Set the interpreter command to be executed at time out. More...

void	SetInterruptSyscalls (Bool_t set=kTRUE)
	When the argument is true the a-synchronous timer (SIGALRM) signal handler is set so that interrupted syscalls will not be restarted by the kernel. More...

void	SetObject (TObject *object)
	Set the object to be notified at time out. More...

void	SetTime (Long_t milliSec)

void	SetTimerID (UInt_t id=0)

virtual void	Start (Long_t milliSec=-1, Bool_t singleShot=kFALSE)
	Starts the timer with a milliSec timeout. More...

virtual void	Stop ()

virtual void	Timeout ()

virtual void	TurnOff ()
	Remove timer from system timer list. More...

virtual void	TurnOn ()
	Add the timer to the system timer list. More...

Public Member Functions inherited from TSysEvtHandler
	TSysEvtHandler ()

virtual	~TSysEvtHandler ()

void	Activate ()
	Activate a system event handler. More...

virtual void	Activated ()

virtual void	Added ()

void	DeActivate ()
	De-activate a system event handler. More...

virtual void	DeActivated ()

Bool_t	IsActive () const

virtual void	Notified ()

virtual void	Removed ()

Public Member Functions inherited from TObject
	TObject ()
	TObject constructor. More...

	TObject (const TObject &object)
	TObject copy ctor. More...

virtual	~TObject ()
	TObject destructor. More...

void	AbstractMethod (const char *method) const
	Use this method to implement an "abstract" method that you don't want to leave purely abstract. More...

virtual void	AppendPad (Option_t *option="")
	Append graphics object to current pad. More...

virtual void	Browse (TBrowser *b)
	Browse object. May be overridden for another default action. More...

virtual const char *	ClassName () const
	Returns name of class to which the object belongs. More...

virtual void	Clear (Option_t *="")

virtual TObject *	Clone (const char *newname="") const
	Make a clone of an object using the Streamer facility. More...

virtual Int_t	Compare (const TObject *obj) const
	Compare abstract method. More...

virtual void	Copy (TObject &object) const
	Copy this to obj. More...

virtual void	Delete (Option_t *option="")
	Delete this object. More...

virtual Int_t	DistancetoPrimitive (Int_t px, Int_t py)
	Computes distance from point (px,py) to the object. More...

virtual void	Draw (Option_t *option="")
	Default Draw method for all objects. More...

virtual void	DrawClass () const
	Draw class inheritance tree of the class to which this object belongs. More...

virtual TObject *	DrawClone (Option_t *option="") const
	Draw a clone of this object in the current selected pad for instance with: `gROOT->SetSelectedPad(gPad)`. More...

virtual void	Dump () const
	Dump contents of object on stdout. More...

virtual void	Error (const char method, const char msgfmt,...) const
	Issue error message. More...

virtual void	Execute (const char method, const char params, Int_t *error=0)
	Execute method on this object with the given parameter string, e.g. More...

virtual void	Execute (TMethod method, TObjArray params, Int_t *error=0)
	Execute method on this object with parameters stored in the TObjArray. More...

virtual void	ExecuteEvent (Int_t event, Int_t px, Int_t py)
	Execute action corresponding to an event at (px,py). More...

virtual void	Fatal (const char method, const char msgfmt,...) const
	Issue fatal error message. More...

virtual TObject *	FindObject (const char *name) const
	Must be redefined in derived classes. More...

virtual TObject *	FindObject (const TObject *obj) const
	Must be redefined in derived classes. More...

virtual Option_t *	GetDrawOption () const
	Get option used by the graphics system to draw this object. More...

virtual const char *	GetIconName () const
	Returns mime type name of object. More...

virtual const char *	GetName () const
	Returns name of object. More...

virtual char *	GetObjectInfo (Int_t px, Int_t py) const
	Returns string containing info about the object at position (px,py). More...

virtual Option_t *	GetOption () const

virtual const char *	GetTitle () const
	Returns title of object. More...

virtual UInt_t	GetUniqueID () const
	Return the unique object id. More...

virtual Bool_t	HandleTimer (TTimer *timer)
	Execute action in response of a timer timing out. More...

virtual ULong_t	Hash () const
	Return hash value for this object. More...

virtual void	Info (const char method, const char msgfmt,...) const
	Issue info message. More...

virtual Bool_t	InheritsFrom (const char *classname) const
	Returns kTRUE if object inherits from class "classname". More...

virtual Bool_t	InheritsFrom (const TClass *cl) const
	Returns kTRUE if object inherits from TClass cl. More...

virtual void	Inspect () const
	Dump contents of this object in a graphics canvas. More...

void	InvertBit (UInt_t f)

virtual Bool_t	IsEqual (const TObject *obj) const
	Default equal comparison (objects are equal if they have the same address in memory). More...

virtual Bool_t	IsFolder () const
	Returns kTRUE in case object contains browsable objects (like containers or lists of other objects). More...

Bool_t	IsOnHeap () const

virtual Bool_t	IsSortable () const

Bool_t	IsZombie () const

virtual void	ls (Option_t *option="") const
	The ls function lists the contents of a class on stdout. More...

void	MayNotUse (const char *method) const
	Use this method to signal that a method (defined in a base class) may not be called in a derived class (in principle against good design since a child class should not provide less functionality than its parent, however, sometimes it is necessary). More...

void	Obsolete (const char method, const char asOfVers, const char *removedFromVers) const
	Use this method to declare a method obsolete. More...

void	operator delete (void *ptr)
	Operator delete. More...

void	operator delete[] (void *ptr)
	Operator delete []. More...

void *	operator new (size_t sz)

void *	operator new (size_t sz, void *vp)

void *	operator new[] (size_t sz)

void *	operator new[] (size_t sz, void *vp)

TObject &	operator= (const TObject &rhs)
	TObject assignment operator. More...

virtual void	Paint (Option_t *option="")
	This method must be overridden if a class wants to paint itself. More...

virtual void	Pop ()
	Pop on object drawn in a pad to the top of the display list. More...

virtual void	Print (Option_t *option="") const
	This method must be overridden when a class wants to print itself. More...

virtual Int_t	Read (const char *name)
	Read contents of object with specified name from the current directory. More...

virtual void	RecursiveRemove (TObject *obj)
	Recursively remove this object from a list. More...

void	ResetBit (UInt_t f)

virtual void	SaveAs (const char filename="", Option_t option="") const
	Save this object in the file specified by filename. More...

virtual void	SavePrimitive (std::ostream &out, Option_t *option="")
	Save a primitive as a C++ statement(s) on output stream "out". More...

void	SetBit (UInt_t f, Bool_t set)
	Set or unset the user status bits as specified in f. More...

void	SetBit (UInt_t f)

virtual void	SetDrawOption (Option_t *option="")
	Set drawing option for object. More...

virtual void	SetUniqueID (UInt_t uid)
	Set the unique object id. More...

virtual void	SysError (const char method, const char msgfmt,...) const
	Issue system error message. More...

Bool_t	TestBit (UInt_t f) const

Int_t	TestBits (UInt_t f) const

virtual void	UseCurrentStyle ()
	Set current style settings in this object This function is called when either TCanvas::UseCurrentStyle or TROOT::ForceStyle have been invoked. More...

virtual void	Warning (const char method, const char msgfmt,...) const
	Issue warning message. More...

virtual Int_t	Write (const char *name=0, Int_t option=0, Int_t bufsize=0)
	Write this object to the current directory. More...

virtual Int_t	Write (const char *name=0, Int_t option=0, Int_t bufsize=0) const
	Write this object to the current directory. More...

Public Member Functions inherited from TQObject
	TQObject ()
	TQObject Constructor. More...

virtual	~TQObject ()
	TQObject Destructor. More...

Bool_t	AreSignalsBlocked () const

Bool_t	BlockSignals (Bool_t b)

virtual void	ChangedBy (const char *method)

void	CollectClassSignalLists (TList &list, TClass *cls)
	Collect class signal lists from class cls and all its base-classes. More...

Bool_t	Connect (const char signal, const char receiver_class, void receiver, const char slot)
	Non-static method is used to connect from the signal of this object to the receiver slot. More...

virtual void	Connected (const char *)

virtual void	Destroyed ()

Bool_t	Disconnect (const char signal=0, void receiver=0, const char *slot=0)
	Disconnects signal of this object from slot of receiver. More...

virtual void	Disconnected (const char *)

template<typename T >
void	Emit (const char *signal, const T &arg)
	Activate signal with single parameter. More...

void	Emit (const char *signal)
	Acitvate signal without args. More...

template<typename... T>
void	EmitVA (const char *signal_name, Int_t, const T &... params)
	Emit a signal with a varying number of arguments. More...

TList *	GetListOfClassSignals () const
	Returns pointer to list of signals of this class. More...

TList *	GetListOfConnections () const

TList *	GetListOfSignals () const

virtual Bool_t	HasConnection (const char *signal_name) const
	Return true if there is any object connected to this signal. More...

virtual void	HighPriority (const char signal_name, const char slot_name=0)

virtual void	LowPriority (const char signal_name, const char slot_name=0)

virtual void	Message (const char *msg)

virtual Int_t	NumberOfConnections () const
	Return number of connections for this object. More...

virtual Int_t	NumberOfSignals () const
	Return number of signals for this object. More...

Static Public Member Functions
static void	SingleShot (Int_t milliSec, const char receiver_class, void receiver, const char *method)
	This static function calls a slot after a given time interval. More...

Static Public Member Functions inherited from TObject
static Long_t	GetDtorOnly ()
	Return destructor only flag. More...

static Bool_t	GetObjectStat ()
	Get status of object stat flag. More...

static void	SetDtorOnly (void *obj)
	Set destructor only flag. More...

static void	SetObjectStat (Bool_t stat)
	Turn on/off tracking of objects in the TObjectTable. More...

Static Public Member Functions inherited from TQObject
static Bool_t	AreAllSignalsBlocked ()
	Returns true if all signals are blocked. More...

static Bool_t	BlockAllSignals (Bool_t b)
	Block or unblock all signals. Returns the previous block status. More...

static Bool_t	Connect (TQObject sender, const char signal, const char receiver_class, void receiver, const char *slot)
	Create connection between sender and receiver. More...

static Bool_t	Connect (const char sender_class, const char signal, const char receiver_class, void receiver, const char *slot)
	This method allows to make a connection from any object of the same class to a single slot. More...

static Bool_t	Disconnect (TQObject sender, const char signal=0, void receiver=0, const char slot=0)
	Disconnects signal in object sender from slot_method in object receiver. More...

static Bool_t	Disconnect (const char class_name, const char signal, void receiver=0, const char slot=0)
	Disconnects "class signal". More...

Protected Attributes
TTime	fAbsTime

TString	fCommand

Bool_t	fIntSyscalls

TObject *	fObject

Bool_t	fSync

TTime	fTime

UInt_t	fTimeID

Bool_t	fTimeout

Protected Attributes inherited from TQObject
TList *	fListOfConnections
	list of signals from this object More...

TList *	fListOfSignals

Bool_t	fSignalsBlocked
	list of connections to this object More...

Private Member Functions
	TTimer (const TTimer &)

TTimer &	operator= (const TTimer &)

Additional Inherited Members
Public Types inherited from TObject
enum	{ kIsOnHeap = 0x01000000, kNotDeleted = 0x02000000, kZombie = 0x04000000, kBitMask = 0x00ffffff }

enum	{ kSingleKey = BIT(0), kOverwrite = BIT(1), kWriteDelete = BIT(2) }

enum	EStatusBits { kCanDelete = BIT(0), kMustCleanup = BIT(3), kObjInCanvas = BIT(3), kIsReferenced = BIT(4), kHasUUID = BIT(5), kCannotPick = BIT(6), kNoContextMenu = BIT(8), kInvalidObject = BIT(13) }

Protected Member Functions inherited from TObject
virtual void	DoError (int level, const char location, const char fmt, va_list va) const
	Interface to ErrorHandler (protected). More...

void	MakeZombie ()

Protected Member Functions inherited from TQObject
virtual const char *	GetSenderClassName () const

Static Protected Member Functions inherited from TQObject
static Int_t	CheckConnectArgs (TQObject sender, TClass sender_class, const char signal, TClass receiver_class, const char *slot)
	Checking of consitency of sender/receiver methods/arguments. More...

static TString	CompressName (const char *method_name)
	Removes "const" words and blanks from full (with prototype) method name and resolve any typedefs in the method signature. More...

static Bool_t	ConnectToClass (TQObject sender, const char signal, TClass receiver_class, void receiver, const char *slot)
	Create connection between sender and receiver. More...

static Bool_t	ConnectToClass (const char sender_class, const char signal, TClass receiver_class, void receiver, const char *slot)
	This method allows to make connection from any object of the same class to the receiver object. More...

Static Protected Attributes inherited from TQObject
static Bool_t	fgAllSignalsBlocked = kFALSE
	flag used for suppression of signals More...

#include <TTimer.h>

Inheritance diagram for TTimer:

[legend]

Constructor & Destructor Documentation

◆ TTimer() [1/4]

TTimer::TTimer ( const TTimer & )

private

◆ TTimer() [2/4]

TTimer::TTimer	(	Long_t	ms = `0`,
		Bool_t	mode = `kTRUE`
	)

Create timer that times out in ms milliseconds.

If milliSec is 0 then the timeout will be the minimum timeout (see TSystem::ESysConstants, i.e. 10 ms). If mode == kTRUE then the timer is synchronous else a-synchronous. The default is synchronous. Add a timer to the system eventloop by calling TurnOn(). Set command to be executed from Notify() or set the object whose HandleTimer() method will be called via Notify(), derive from TTimer and override Notify() or connect slots to the signals Timeout(), TurnOn() and TurnOff().

Definition at line 86 of file TTimer.cxx.

◆ TTimer() [3/4]

TTimer::TTimer	(	TObject *	obj,
		Long_t	ms,
		Bool_t	mode = `kTRUE`
	)

Create timer that times out in ms milliseconds.

If mode == kTRUE then the timer is synchronous else a-synchronous. The default is synchronous. Add a timer to the system eventloop by calling TurnOn(). The object's HandleTimer() will be called by Notify().

Definition at line 101 of file TTimer.cxx.

◆ TTimer() [4/4]

TTimer::TTimer	(	const char *	command,
		Long_t	ms,
		Bool_t	mode = `kTRUE`
	)

Create timer that times out in ms milliseconds.

If mode == kTRUE then the timer is synchronous else a-synchronous. The default is synchronous. Add a timer to the system eventloop by calling TurnOn(). The interpreter will execute command from Notify().

Definition at line 116 of file TTimer.cxx.

◆ ~TTimer()

virtual TTimer::~TTimer ( )

inlinevirtual

Definition at line 71 of file TTimer.h.

Member Function Documentation

◆ Add()

void TTimer::Add ( )

inlinevirtual

Implements TSysEvtHandler.

Definition at line 84 of file TTimer.h.

◆ CheckTimer()

Bool_t TTimer::CheckTimer ( const TTime & now )

Check if timer timed out.

Definition at line 128 of file TTimer.cxx.

◆ GetAbsTime()

TTime TTimer::GetAbsTime ( ) const

inline

Definition at line 78 of file TTimer.h.

◆ GetCommand()

const char* TTimer::GetCommand ( ) const

inline

Definition at line 74 of file TTimer.h.

◆ GetObject()

TObject* TTimer::GetObject ( )

inline

Definition at line 75 of file TTimer.h.

◆ GetTime()

TTime TTimer::GetTime ( ) const

inline

Definition at line 76 of file TTimer.h.

◆ GetTimerID()

UInt_t TTimer::GetTimerID ( )

inline

Definition at line 77 of file TTimer.h.

◆ HasTimedOut()

Bool_t TTimer::HasTimedOut ( ) const

inline

Definition at line 79 of file TTimer.h.

◆ IsAsync()

Bool_t TTimer::IsAsync ( ) const

inline

Definition at line 81 of file TTimer.h.

◆ IsInterruptingSyscalls()

Bool_t TTimer::IsInterruptingSyscalls ( ) const

inline

Definition at line 82 of file TTimer.h.

◆ IsSync()

Bool_t TTimer::IsSync ( ) const

inline

Definition at line 80 of file TTimer.h.

◆ Notify()

Bool_t TTimer::Notify ( )

virtual

Notify when timer times out.

The timer is always reset. To stop the timer call TurnOff(). Make sure to call Reset() also in derived Notify() so timers will keep working repeatedly.

Implements TSysEvtHandler.

Reimplemented in TIdleTOTimer, TReaperTimer, TShutdownTimer, TGLRedrawTimer, TProcessEventTimer, TThreadTimer, and TViewTimer.

Definition at line 143 of file TTimer.cxx.

◆ operator=()

TTimer& TTimer::operator= ( const TTimer & )

private

◆ Remove()

void TTimer::Remove ( )

inlinevirtual

Implements TSysEvtHandler.

Definition at line 85 of file TTimer.h.

◆ Reset()

void TTimer::Reset ( void )

Reset the timer.

Definition at line 157 of file TTimer.cxx.

◆ SetCommand()

void TTimer::SetCommand ( const char * command )

Set the interpreter command to be executed at time out.

Removes the object to be notified (if it was set).

Definition at line 174 of file TTimer.cxx.

◆ SetInterruptSyscalls()

void TTimer::SetInterruptSyscalls ( Bool_t set = kTRUE )

When the argument is true the a-synchronous timer (SIGALRM) signal handler is set so that interrupted syscalls will not be restarted by the kernel.

This is typically used in case one wants to put a timeout on an I/O operation. By default interrupted syscalls will be restarted.

Definition at line 197 of file TTimer.cxx.

◆ SetObject()

void TTimer::SetObject ( TObject * object )

Set the object to be notified at time out.

Removes the command to be executed (if it was set).

Definition at line 184 of file TTimer.cxx.

◆ SetTime()

void TTimer::SetTime ( Long_t milliSec )

inline

Definition at line 90 of file TTimer.h.

◆ SetTimerID()

void TTimer::SetTimerID ( UInt_t id = 0 )

inline

Definition at line 91 of file TTimer.h.

◆ SingleShot()

void TTimer::SingleShot	(	Int_t	milliSec,
		const char *	receiver_class,
		void *	receiver,
		const char *	method
	)

static

This static function calls a slot after a given time interval.

Created internal timer will be deleted after that.

Definition at line 256 of file TTimer.cxx.

◆ Start()

void TTimer::Start	(	Long_t	milliSec = `-1`,
		Bool_t	singleShot = `kFALSE`
	)

virtual

Starts the timer with a milliSec timeout.

If milliSec is 0 then the timeout will be the minimum timeout (see TSystem::ESysConstants, i.e. 10 ms), if milliSec is -1 then the time interval as previously specified (in ctor or SetTime()) will be used. If singleShot is kTRUE, the timer will be activated only once, otherwise it will continue until it is stopped. See also TurnOn(), Stop(), TurnOff().

Definition at line 211 of file TTimer.cxx.

◆ Stop()

virtual void TTimer::Stop ( )

inlinevirtual

Reimplemented in TGLRedrawTimer.

Definition at line 93 of file TTimer.h.

◆ Timeout()

virtual void TTimer::Timeout ( )

inlinevirtual

Definition at line 96 of file TTimer.h.

◆ TurnOff()

void TTimer::TurnOff ( )

virtual

Remove timer from system timer list.

This requires that a timer has been placed in the system timer list (using TurnOn()). If a TTimer subclass is placed on another list, override TurnOff() to remove the timer from the correct list.

Definition at line 229 of file TTimer.cxx.

◆ TurnOn()

void TTimer::TurnOn ( )

virtual

Add the timer to the system timer list.

If a TTimer subclass has to be placed on another list, override TurnOn() to add the timer to the correct list.

Definition at line 241 of file TTimer.cxx.

Member Data Documentation

◆ fAbsTime

TTime TTimer::fAbsTime

protected

Definition at line 55 of file TTimer.h.

◆ fCommand

TString TTimer::fCommand

protected

Definition at line 61 of file TTimer.h.

◆ fIntSyscalls

Bool_t TTimer::fIntSyscalls

protected

Definition at line 58 of file TTimer.h.

◆ fObject

TObject* TTimer::fObject

protected

Definition at line 60 of file TTimer.h.

◆ fSync

Bool_t TTimer::fSync

protected

Definition at line 57 of file TTimer.h.

◆ fTime

TTime TTimer::fTime

protected

Definition at line 54 of file TTimer.h.

◆ fTimeID

UInt_t TTimer::fTimeID

protected

Definition at line 59 of file TTimer.h.

◆ fTimeout

Bool_t TTimer::fTimeout

protected

Definition at line 56 of file TTimer.h.

The documentation for this class was generated from the following files:

core/base/inc/TTimer.h
core/base/src/TTimer.cxx

Public Member Functions

Static Public Member Functions

Protected Attributes

Private Member Functions

Additional Inherited Members

Constructor & Destructor Documentation

◆ TTimer() [1/4]

◆ TTimer() [2/4]

◆ TTimer() [3/4]

◆ TTimer() [4/4]

◆ ~TTimer()

Member Function Documentation

◆ Add()

◆ CheckTimer()

◆ GetAbsTime()

◆ GetCommand()

◆ GetObject()

◆ GetTime()

◆ GetTimerID()

◆ HasTimedOut()

◆ IsAsync()

◆ IsInterruptingSyscalls()

◆ IsSync()

◆ Notify()

◆ operator=()

◆ Remove()

◆ Reset()

◆ SetCommand()

◆ SetInterruptSyscalls()

◆ SetObject()

◆ SetTime()

◆ SetTimerID()

◆ SingleShot()

◆ Start()

◆ Stop()

◆ Timeout()

◆ TurnOff()

◆ TurnOn()

Member Data Documentation

◆ fAbsTime

◆ fCommand

◆ fIntSyscalls

◆ fObject

◆ fSync

◆ fTime

◆ fTimeID

◆ fTimeout