Hi,

in order to get the data out of these root files I did:

open root file on the command line
   :~> root filename.root

in root I checked the contents of the file using
   .ls

I see that there is a TH1F inside and I can also see its name --> histname
then I get a pointer to that histo

   TH1F *h = _file0.Get("histname");

then I open an output text file:
   
   ofstream myfile;
   myfile.open("output_file_name.txt");

now just loop over the histogram bins...
   for (int i = 1; 1<301; i++) {
   myfile << i << "\t" << h->GetBinContent(i) << endl;
   }
   myfile.close();


that's it ...