Using Arduino as a pc remote controller I would like to create a simple remote controller (IR) with my Arduino Nano that would control my PC. (Volume up/down, stop, play and that sort of things...) 
I have no problem with creating 'hardware part' and Arduino script, that would send commands through serial as a reaction to IR signals.
I can imagine python script that would react to commands received on the serial port.

My problem is: "How can I detect on which port should I listen to?" What is the right way to do it?
Since I can not commemnt due to low reputation, I'm "commenting" here. 
You can search for LIRC and WinLIRC