Error when DISPLAY not set

[steob92]

I'm not sure if this is an ED issue or a ROOT issue. Nonetheless its worth report at least as a known issue.

We've (@leandrorizk) been debugging issues at McGill when running evndisp, not finding dictionaries, for example:

Warning in <UnknownClass::SetDisplay>: DISPLAY not set, setting it to IP:0.0
Error in <TCling::RegisterModule>: Cannot open shared library /raid/reedbuck/lrizk/Eventdisplay/EventDisplay_v4/bin/evndisp for dictionary VPlotUtilities_Dict:
  /raid/reedbuck/lrizk/Eventdisplay/EventDisplay_v4/bin/evndisp: cannot dynamically load position-independent executable
Error in <TCling::RegisterModule>: Cannot open shared library /raid/reedbuck/lrizk/Eventdisplay/EventDisplay_v4/bin/evndisp for dictionary VEvndispRunParameter_Dict:
  /raid/reedbuck/lrizk/Eventdisplay/EventDisplay_v4/bin/evndisp: cannot dynamically load position-independent executable
Error in <TCling::RegisterModule>: Cannot open shared library /raid/reedbuck/lrizk/Eventdisplay/EventDisplay_v4/bin/evndisp for dictionary VGlobalRunParameter_Dict:
  /raid/reedbuck/lrizk/Eventdisplay/EventDisplay_v4/bin/evndisp: cannot dynamically load position-independent executable
Error in <TCling::RegisterModule>: Cannot open shared library /raid/reedbuck/lrizk/Eventdisplay/EventDisplay_v4/bin/evndisp for dictionary VEvndispReconstructionParameter_Dict:
  /raid/reedbuck/lrizk/Eventdisplay/EventDisplay_v4/bin/evndisp: cannot dynamically load position-independent executable
Error in <TCling::RegisterModule>: Cannot open shared library /raid/reedbuck/lrizk/Eventdisplay/EventDisplay_v4/bin/evndisp for dictionary VImageCleaningRunParameter_Dict:
  /raid/reedbuck/lrizk/Eventdisplay/EventDisplay_v4/bin/evndisp: cannot dynamically load position-independent executable
Error in <TCling::RegisterModule>: Cannot open shared library /raid/reedbuck/lrizk/Eventdisplay/EventDisplay_v4/bin/evndisp for dictionary VEffectiveAreaCalculatorMCHistograms_Dict:
  /raid/reedbuck/lrizk/Eventdisplay/EventDisplay_v4/bin/evndisp: cannot dynamically load position-independent executable

The Error in <TCling::RegisterModule>: Cannot open shared library appears to be misleading, the error is related to the first line:

Warning in <UnknownClass::SetDisplay>: DISPLAY not set, setting it to IP:0.0

I've removed the IP form above. After some tireless debugging from our sysadmin, setting DISPLAY to anything, even an empty string, resolves the issue.

[GernotMaier]

Sorry for not replying earlier. Not sure what I can do. The issue with display/root/xwindows being difficult to set is around for a while. root has an option to display in a browser without using xwindows, but I never tried it.

[steob92]

No worries.

Yeah I suspect its mostly a ROOT issue, but it was non-trivial to debug so worth reporting for future debuggers. I've used the web browser for TBrowsers but I think this is related to just graphics in general. Some maybe anything that uses a ROOT-based GUI or TCanvas for plotting might see a similar issue.

[GernotMaier]

Thanks. Do we want to close this issue then? Open issues make me nervous, at it usually means that I have to do something...