Mac OsX terminal window has powerful features than any other operating systems but if you are working on a remote server you need to know a little more about it.
If you are using MacOSX and if you are connecting lxplus@cern using regular command ssh, the first thing you will observe is that your system cannot open X11 window which is needed by ROOT. To overcome this problem, you should connect using either
ssh -X username@lxplus.cern.ch
or
ssh -Y username@lxplus.cern.ch
X option, provides you a ssh connection forwarding X11. And Y option, provides a ssh connection Forwarding trusted X11.
After you logged in using your user name and password, you have 2 options to run ROOT.
1 -) Entering ROOT variables below:
export ROOTSYS=/afs/cern.ch/sw/lcg/external
/root/5.14.00/slc4_ia32_gcc34/root/
export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:$ROOTSYS/lib
export PATH=$PATH:$ROOTSYS/bin
2-) Or just source Athena Framework as: (It actually consists much more than ROOT)
source cmthome/setup.sh -tag=15.6.4,setup,32
–Recently this procedure has been changed and became eaiser. Please google for sourcing Athena framework–
Then just write “root” and start your analysis.
Posted by Kuday 
