I have rough plumbing installed in the basement; it’s “rough” because all the pipes are there but just no fixtures. the vent pipe (open) I believe is connected to the venting system in the house. So in winter, the pipe smell bad and sometimes drips water (from condensation, I think); Should this vent pipe be connected to the other vents? or should it have a trap or something else to simulate a working fixture? Please help.
Most of the better codes frown upon DEAD ENDS (piping not used for admitting air or liquid with a developed of 24″ or more)
Yes, indeed your vent should be connected and a trap should be installed and either filled with water OR the inlet of the trap plugged/cappped until you decide to do the FINISH plumbing aspect .