Problems with TBranchOld

ROOT
1

Hi ,
I’m trying to read an ASCII file and fill in a Tree some data and ojects; the single data doesn’t worry me at all , but with the object I’m getting trouble. Here is the part of the code who caused the segmentation violation during the run of the executable(compilation is ok)

#include “io_gcc.hh”
#include “Track.hh”
#include “HitsEvent.hh”
#include “OfflineTrigger.hh”

#include “TFILE.h”
#include “TH1.h”
#include “TFile.h”
#include “TTree.h”
#include “TBranch.h”

int main(int argc, char *argv[])
{
TFile *outputfile = new TFile(“prova.root”,“RECREATE”);
TTree *ttr = new TTree(“ttr”,“Physics”);

TBranch *bra = ttr->BranchOld(“neutrino”,“Neutrino”,&nu,4000,1);
//makes me problem

ttr->Branch(“num_hit”,&num_hit,“num_hit/i”);
//does work
…
…
…
and here is the output during the run

*** Break *** segmentation violation
Generating stack trace…
0x003061e8 in G__CallFunc::Exec(void*) + 0x6e from /usr/local/root/lib/libCint.so
0x00c33e2b in TClass::BuildRealData(void*) + 0x2f7 from /usr/local/root/lib/libCore.so
0x00803571 in TTree::BuildStreamerInfo(TClass*, void*) + 0x31 from /usr/local/root/lib/libTree.so
0x007e9577 in TBranchObject::TBranchObject[in-charge](char const*, char const*, void*, int, int, int) + 0xb7 from /usr/local/root/lib/libTree.so
0x00801fd1 in TTree::BranchOld(char const*, char const*, void*, int, int) + 0x8f from /usr/local/root/lib/libTree.so
0x08050708 in main + 0x3d0 from ./analisi
0x0838d770 in __libc_start_main + 0xf0 from /lib/tls/libc.so.6
0x080502a9 in __gxx_personality_v0 + 0x1b1 from ./analisi
Aborted

2

Hi,

We do not recommend using BranchOld directly.
(Use Branch instead).

Also what is ‘v’? The 3rd argument to BranchOld
(and Branch when using objects) is supposed to
be the address of a pointer (You probably meant
&v).

Cheers.
Philippe.

3

Hi and thanks for your reply

v is wrong , instead I got &nu in my code
I defined a pointer (*nu) to a class Neutrino, that holds all the physical information that I’m getting from the file

#include “TFILE.h”
#include “TH1.h”
#include “TFile.h”
#include “TTree.h”
#include “TBranch.h”

int main(int argc, char *argv[])
{
int num_hit;
Neutrino *nu;
TFile *outputfile = new TFile(“prova.root”,“RECREATE”);
TTree *ttr = new TTree(“ttr”,“Physics”);

ttr->Branch(“neutrino”,“Neutrino”,&nu,4000,1);
//makes still problems

ttr->Branch(“num_hit”,&num_hit,“num_hit/i”);
//does work

how can I manage an entire object with Branch?

4

sorry “&nu” not &nu

5

I mean “adress of nu”!

6

Instaed of
Neutrino *nu;
you should preset your pointer to 0
Neutrino *nu=0;

Rene

7

Thanks to all,
my program is now working fine , using only Branch and with the presetted pointer…
and including some libraries that I forgot…!
bye