Reading strings from a tree?

From: stefan kluth (skluth@mh1.lbl.gov)
Date: Tue Jul 28 1998 - 02:52:20 MEST 

Hello,

I try to write strings into a tree (and to read them back of course!). I
seem to be able to write strings ok, but I can't read them back. Here is
what I do:

...

  TFile myfile( "treetest.root", "RECREATE" );
  TTree* tree = new TTree( "tree", "ROOT test tree" );
  char* ach;
  TBranch* brach= tree->Branch( "ach", (void*)ach, "ach/C", 8000 );

... now loop and fill ach with different strings, works ok. 

Then I do in root (2.00/08):

root [0] #include <iostream.h>
root [1] TFile myfile( "treetest.root");
root [2] myfile.ls();
TFile**         treetest.root
 TFile*         treetest.root
  KEY: TTree    tree;1 ROOT test tree
root [3] TBranch *brach  = tree.GetBranch("ach");
root [4] char* ach;
root [5] brach->SetAddress(ach);
root [6] tree.GetEvent(3);
root [7] cout << ach << endl; 

root [8]


So, somehow the strings stored in the tree branch "ach" don't get assigned
to the char* ach. 

Any ideas as what am I doing wrong here?

cheers, Stefan

---Stefan Kluth---------------Lynen Fellow----------------|\--|\-------
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