Ttimer in a standalone application

i would like to use TTimer in a standalone C++ application. I copy, compile and execute the following example:

with the correction given at the end by bellenot.
However it still does “not work” on my computer, i.e.
i expected that the function DAQMainFrame::HandleTimer() is called every 100ms,
but this is not the case and when i click on “Close windows” i get a crash.

Here is the code i wrote:

#include <iostream>

#include <TApplication.h>
#include <TCanvas.h>
#include <TTimer.h>

#include <TGClient.h>
#include <TGFrame.h>
#include <TRootEmbeddedCanvas.h>

using namespace std;

class DAQMainFrame : public TGMainFrame{
	TApplication* daqApp;
	TRootEmbeddedCanvas* canvas;
	TTimer* timer;
	virtual ~DAQMainFrame();
	Bool_t HandleTimer(TTimer*);
DAQMainFrame::DAQMainFrame(TApplication* app) : TGMainFrame(gClient->GetRoot()){
	//I get this notification, and the window opens
	cout<<"DAQMainFrame constructor called\n";
	daqApp = app;
	canvas = new TRootEmbeddedCanvas("Ecanvas",this,800,600);
	AddFrame(canvas, new TGLayoutHints(kLHintsExpandX | kLHintsExpandY, 10,10,10,1));

	SetWindowName("TPTPC DAQ");
	timer = new TTimer(this, 100);//create a TTimer to call the frame's HandleTimer(TTimer*)

DAQMainFrame::~DAQMainFrame() {
	//I get this notification when the window closes
	cout<<"DAQMainFrame destructor called\n";

Bool_t DAQMainFrame::HandleTimer(TTimer*){
	//I never actually get this notification
	cout<<"DAQMainFrame::HandleTimer called\n";
	return kTRUE; 

int main(){
	TApplication* daqApp = new TApplication("daqApp",0,0);
	new DAQMainFrame(daqApp);
	return 0;

Here is the output of the program:
DAQMainFrame constructor called

I expected that the function DAQMainFrame::HandleTimer() is called every 100ms,
but this is not the case.
And when i click on “Close windows” i get the error:

There was a crash.
This is the entire stack trace of all threads:
#0  0x00007f5d80f1207a in __GI___waitpid (pid=11096, stat_loc=stat_loc
entry=0x7ffea575f840, options=options
entry=0) at ../sysdeps/unix/sysv/linux/waitpid.c:29
#1  0x00007f5d80e8afbb in do_system (line=<optimized out>) at ../sysdeps/posix/system.c:148
#2  0x00007f5d82280dd4 in TUnixSystem::StackTrace() () from /usr/lib/x86_64-linux-gnu/
#3  0x00007f5d8228303c in TUnixSystem::DispatchSignals(ESignals) () from /usr/lib/x86_64-linux-gnu/
#4  <signal handler called>
#5  0x0000000000406ac6 in DAQMainFrame::~DAQMainFrame() ()
#6  0x00007f5d81b1af7a in ?? () from /usr/lib/x86_64-linux-gnu/
#7  0x00007f5d806077bb in Cint::G__CallFunc::Execute(void*) () from /usr/lib/x86_64-linux-gnu/
#8  0x00007f5d8224364c in TCint::CallFunc_Exec(void*, void*) const () from /usr/lib/x86_64-linux-gnu/
#9  0x00007f5d821cbb73 in TQConnection::ExecuteMethod() () from /usr/lib/x86_64-linux-gnu/
#10 0x00007f5d82219ce9 in TQObject::Emit(char const*) () from /usr/lib/x86_64-linux-gnu/
#11 0x00007f5d82223997 in TTimer::Notify() () from /usr/lib/x86_64-linux-gnu/
#12 0x00007f5d822238c1 in TTimer::CheckTimer(TTime const&) () from /usr/lib/x86_64-linux-gnu/
#13 0x00007f5d82282f79 in TUnixSystem::DispatchTimers(bool) () from /usr/lib/x86_64-linux-gnu/
#14 0x00007f5d82283485 in TUnixSystem::DispatchOneEvent(bool) () from /usr/lib/x86_64-linux-gnu/
#15 0x00007f5d821f3904 in TSystem::InnerLoop() () from /usr/lib/x86_64-linux-gnu/
#16 0x00007f5d821f1bdf in TSystem::Run() () from /usr/lib/x86_64-linux-gnu/
#17 0x00007f5d8221de1f in TApplication::Run(bool) () from /usr/lib/x86_64-linux-gnu/
#18 0x0000000000406cbc in DAQMainFrame::DAQMainFrame(TApplication*) ()
#19 0x00000000004068b2 in main ()

The lines below might hint at the cause of the crash.
If they do not help you then please submit a bug report at Please post the ENTIRE stack trace
from above as an attachment in addition to anything else
that might help us fixing this issue.
#5  0x0000000000406ac6 in DAQMainFrame::~DAQMainFrame() ()
#6  0x00007f5d81b1af7a in ?? () from /usr/lib/x86_64-linux-gnu/

DAQMainFrame destructor called

 *** Break *** segmentation violation
^CDAQMainFrame destructor called

 *** Break *** segmentation violation

Thank you in advance,
Best regards,
Frédéric Faure.

_ROOT Version: 5.34
_Platform: Ubuntu 16.04
_Compiler: g++ 5.4

You forgot to remove daqApp->Run(); from the DAQMainFrame constructor…

Thank you very much,
i am sorry for my wrong message.

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