# Install HYDRA
 1. `git clone https://git.gsi.de/hades-software/hydra2.git`
 2. `cd hydra2`
 3. `cp admin/*.mk admin/Makefile .`
 4. `cp admin/defall.sh .`
 5. `cp scripts/packages/admin/hsc-functions.sh .`
 6. Modify your defall.sh script (see section below)
 7. `source defall.sh`
 8. Edit you Makefile
    ```
    INSTALL_DIR        ?= absolute_path_to_my_install_Dir # should match $HADDIR
    export USES_ORACLE ?= yes  # "yes" if ORACLE client is available, "no" to compile without
    ```
 9. `make build -s -j8` #  -s : reduce print output, -j8 compile with 8 processes parallel
10. `make install`      #  move the finished librarys and header files to the INSTALL_DIR

# Run HYDRA
Running Root with hydra2 libs preloaded:

You need to setup  a .rootrc file in your HOME dir:
Our rootlogon.C will load all libs and set compiler
path vars to alow full usage of out librarys in a root
session. To work correctly root should know rootlogon.C
to start it automatically with a new root session:
```
Unix.*.Root.MacroPath: .:$(MYHADDIR)/macros:$(HADDIR)/macros
TFile.Recover:         no
Rint.Logon:            rootlogon.C
```

To start Root :

`root  -l` # you will get print out from the rootlogon.C about loaded libs

# Setting up defall.sh
1. Edit `ROOTSYS` and `HADDIR` according to your root and hydra installation directory.
2. Edit `ORACLE_HOME/ORA_USER` if you have your own ORACLE client installation.
   If you do not have an ORACLE client installation available ignore this variables and use to compile without ORACLE support later.
3. `CERN_ROOT` is needed for [HGeant2](https://git.gsi.de/hades-software/hgeant2) compilation only, for Hydra2 build it can be ignored.
4. `PLUTODIR` can be set to the PLUTO installation directory to load at the start of a root session automatically.
   For pure Hydra2 it can be ignored.
5. The  the path to `hsc-functions.sh` has to be setup correctly.
   On the preinstalled versions on `/cvmfs/hadessoft.gsi.de` we use a common place, but you can use your local copy as well.

Example defall.sh (debian12, root 6.36.02) installed on `/cvmfs/hadessoft.gsi.de/install/debian12/6.36.02/hydra2-7.4/defall.sh`:
```
###############################################################################
#
#  Hades Software Environment Setup Script (Bourne shell family version)
#
#  Each Software Collection should have it dedicated verion of this script.
#  They can be distinguished e.g. by the used paths.
#
#  Author: Simon Lang, GSI, 30.09.2006
#
###############################################################################

. /cvmfs/hadessoft.gsi.de/install/debian12/admin/hsc-functions.sh

hsc_checkContext

# Root, and dependent packages
export ROOTSYS=/cvmfs/hadessoft.gsi.de/install/debian12/root-6.36.02

# Global Hydra Location
export HADDIR=/cvmfs/hadessoft.gsi.de/install/debian12/6.36.02/hydra2-7.4
export ROOT_INCLUDE_PATH=${HADDIR}/include

# Private Hydra Location - not used by default
#export MYHADDIR=/e.g./somewhere/in/my/home/directory
#export ROOT_INCLUDE_PATH=${MYHADDIR}/include:${HADDIR}/include

# Oracle
export ORACLE_HOME=/cvmfs/hadessoft.gsi.de/install/debian12/oracle/client
export ORA_USER=hades_ana/hades@db-hades

# CERNLIB - for HGeant
export CERN_ROOT=/cvmfs/hadessoft.gsi.de/install/debian12/cernlib_gfortran/2005

# PLUTO
export PLUTODIR=

hsc_setEnvironment
hsc_shortPrintout

hsc_finalizeScript

-------------------------------------------------------------------------------
```