Note that this is not a Xcode extension, but an unofficial plugin. It will only work if you unsign Xcode. Or if you need a minimal logging tool to produce the logs you saw at the top, I included one ...
Please note that plugins are not supported by Xcode 8. See alcatraz/Alcatraz#475 for more information. If you are using Swift, Copy Logger.swift to you project. If ...
OK, this may seem like the clueless n00b question of the century ... but in Project Builder or xCode it seems to be a misery to debug any code for "simple tools" (aka ordinary stdio applications) ...