Cross-platform check for port in use - windows

Question

I'm looking for a cross-platform way to check if a port is in use so I can print a warning message.
I have accomplished this in macOS:
if lsof -Pi :8080 -sTCP:LISTEN -t >/dev/null; then
echo "Port 8080 is already in use"
fi
But this bash script needs to also work on Windows machines. I was looking at something like netstat -aon | find "8080", but I'm unsure how to use that in my script (don't have a Windows machine).
Is there an efficient way to do this? If it helps, the Windows machines have WSL available to them (but lsof doesn't appear to work yet).

Answer 1

While I'm certain the other answers would work in certain situations, I just wanted to note I ended up going with the following solution for my own work:
if echo PING | nc localhost 8080 >/dev/null; then
echo "Port 8080 in use"
fi

Answer 2

Im not sure how your network looks like but maybe nmap will be a solution for you. You can scan ports for every pc in your local network using only linux.
If port is open, that mean is in use. This solution will work for any system.
apt-get install nmap
for example like this:
if nmap -p 8080 <ip address> | grep -wq "open"
then
echo "Port 8080 is already in use"
fi

Answer 3

Use netstat (works on windows, mac, wsl2)
Example netstat -a | grep :8080 where 8080 is the port you are interested in.
If you are on wsl1 you will need to use the windows netstat as the one included in wsl is broken. Simply set an alias to the windows netstat before using it alias netstat='/mnt/c/Windows/System32/netstat.exe'