Unexpected message from ROOT
If you run:
unset DISPLAY art -c /dev/null
you will find the following among the art output:
%MSG %MSG-i Root_Information: art TUnixSystem::SetDisplay() 04-Feb-2016 14:09:37 CST JobSetup DISPLAY not set, setting it to mac-121205.dhcp.fnal.gov:0.0 %MSG
According to Philippe something inside art has directly, or indirectly, triggered ROOT to think that it needs to be ready to use X11. So it checks DISPLAY and, if it finds that DISPLAY is undefined, it takes the action described in the message and sends the message.
It's not clear if we need to fix anything here - but we need to ask the question and get an answer.
According two Philippe we have four options:
- Figure out what is triggering the action and, if appropriate remove it.
- call gROOT->SetBatch(kTRUE) early in the job.
- export DISPLAY=""
- live with it; it's not harmful
My own feeling is that we do not want to do 2) because modules should be free to use ROOT's X11 graphics and this may interfere. If 1) is little work, then do it; if not then I vote for 4).
#1 Updated by Kyle Knoepfel almost 4 years ago
- Status changed from New to Remission
We have communicated with Mu2e. We are unable to reproduce this error in our environments. If Mu2e turns up additional information re. what ROOT configuration options should be used to avoid this, we would appreciate knowing.