Find that program running on that port

macOS (tested on 10.11.6):
sudo lsof -i :80
…where ’80’ is the port you’re curious about (substitute any value)

Thanks to Databasically.

Windows (tested on 10 Pro version 1709):
netstat -ano
…this will produce a list of ports in use and the PIDs using them)

Thanks to @RickVanover.

Fedora 20
netstat -npl | grep 8013
…this will find the name of the process running on port 8013. Thanks to Vivek Gite at nixCraft.

Writing reliable Windows Batch files

This is probably a good argument to just ditch Windows Batch (.bat) files entirely for Windows Powershell scripts, but if you find yourself in a position where this is not feasible, see this Stack Overflow post about how to check the exit codes of programs run within Windows Batch files.

How to remove or uninstall software on Windows 10

1. Tap/click Start > Settings (gear icon) > Apps
2. Locate the app to uninstall and tap/click it.
3. Tap/click Uninstall

Note: Note: these instructions were written using Windows 10 Pro Version 1703 OS Build 15063.0. To see what version of Windows 10 you are using, select Start > Settings (gear icon) > About.

Mac files, Windows and removable media

A good post on this topic by Brian Dickens over at HostileFork: http://blog.hostilefork.com/trashes-fseventsd-and-spotlight-v100/

If you’re reading this, you have probably found some USB stick or external drive with files named .Trashes, .fseventsd, .Spotlight-V100 (and possibly even the more rarely reported ._.Trashes) on it. You might also be annoyed to see files in various directories called .DS_Store. Right?