//================================================
// Using TFileMerger
//================================================
root [0]  TFileMerger a;
root [1]   a.AddFile("w+2b.1.root");
[TFile::Cp] Total 7.49 MB       |====================| 100.00 % [145.6 MB/s]
root [2]   a.AddFile("w+2c.2.root");
[TFile::Cp] Total 11.02 MB      |====================| 100.00 % [157.0 MB/s]
root [3]   a.AddFile("tt_lj.3.root");
[TFile::Cp] Total 1.21 MB       |====================| 100.00 % [155.9 MB/s]
root [4]   a.AddFile("tt_dl.4.root");
[TFile::Cp] Total 14.99 MB      |====================| 100.00 % [169.7 MB/s]
root [5]   a.AddFile("qcd.7.root");
[TFile::Cp] Total 0.15 MB       |====================| 100.00 % [64.6 MB/s]
root [6]   a.AddFile("w+lp.0.root");
[TFile::Cp] Total 39.07 MB      |====================| 100.00 % [63.2 MB/s]
root [7]  a->Merge();
Info in <TFileMerger::Merge>: will merge the results to the file FileMerger.root
in your working directory, since you didn't specify a merge filename
Info in <TFileMerger::MergeRecursive>: merging tree myCcProcessFactory.DlMyFactoryDecisionTool.myCcProcessFactory.DlMyFactoryDecisionTool.DlDecisionTNtuple
Error: G__getvariable: expression  (tmpfile):1:
Error: Can not access pointer to function 0x0 from interpreter(1) FILE:(tmpfile) LINE:1
Error: $(*)187696320  Syntax error? (tmpfile):1:
Syntax Error: * (tmpfile):1:
Error: Illegal pointer operation (tovalue) (tmpfile):1:
Error: memory allocation for  (*(*)187696320) size=4 pinc=1 FILE:(tmpfile) LINE:1
*** Interpreter error recovered ***
root [8] .q
//================================================
// Using TChain
//================================================
root [0] TChain ch("myCcProcessFactory.DlMyFactoryDecisionTool.myCcProcessFactory.DlMyFactoryDecisionTool.DlDecisionTNtuple")
root [1] ch.Add("w+2b.1.root")
(Int_t)1
root [2] ch.Add("w+2c.2.root")
(Int_t)1
root [3] ch.Add("tt_lj.3.root")
(Int_t)1
root [4] ch.Add("tt_dl.4.root")
(Int_t)1
root [5] ch.Add("qcd.7.root")
(Int_t)1
root [6] ch.Add("w+lp.0.root")
(Int_t)1
root [7] ch.Merge("newfile.root")
Syntax Error: * (tmpfile):1:
Error: Illegal pointer operation (tovalue) (tmpfile):1:
(Long64_t)0
*** Interpreter error recovered ***