Openmc.lib open pseudoterminals

Hi,
I’ve noticed that when running openmc in memory from the python API using the openmc.lib module, with the output parameter set to False, a new pseudo-terminal (/dev/pts/) gets created.

To reproduce:

openmc.lib.init()
openmc.lib.run(**{'output':False})

image

I’ve noticed this behavior by running a very long search_for_keff in memory and hitting the max open file limits of my system.

Is this expected?

p.s. If I set the output to True or if I don’t run in memory this does not happen.