How to link with GEANT part of ROOT

Witold Przygoda (Witold.Przygoda@Physik.Tu-Muenchen.DE)
Mon, 6 Jul 1998 19:34:57 +0200 (MDT)


Hallo!

I would like to do maybe a strange thing: once I am get rid of
HBOOK file format (CWN-ntuples) which I get from my GEANT
simulations, I have decided to try to link part of ROOT so to be
able to write data directly into ROOT-file format.

I wrote a piece of code in C++ which contains some
functions maintaining opening file/creating tree,branches/fillig
and I wrapped these functions with usage of cfortran.h
Then I linked everything together (plus root libraries).
Once I run my geant exec (it calls in UHBOOK part of simulation
my function opening file and creating tree etc.) I get:

Fatal in <TFile::TFile>: ROOT system not initialized
aborting
forrtl: error (76): IOT trap signal
Resources lost

What does it mean? How (where) ought I to initialize ROOT system
(the underlying question is of course - can I somehow
write my simulation data directly to root-file).

Best regards,
and thanks in anticipation for help

Witold Przygoda