Running a bash script as a mac .app

example.sh

#!/bin/bash
THIS_FOLDER="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"

# basically ./actual_binary but using a proper path
"${THIS_FOLDER}/actual_binary"

instructions.md

• Consider a game.app with a game binary inside
• Rename the binary file inside Contents/MacOS/game - let's say Contents/MacOS/thegame
• Create a new empty file where the binary was Contents/MacOS/game
• Put the example.sh bash code inside of it.
• Change it to run thegame instead of actual_binary
• make the new script executable with chmod +x Contents/MacOS/game
  • warning this permission can get stripped away on windows, zips, http etc.
• That's it!

notes

The machination is: Info.plist has:

<key>CFBundleExecutable</key>
<string>game</string>

This tells the app what to run when double clicked.
Point it to a bash script that runs the game (and does other work ahead of that).

other notes

• watch out for paths not being relative
• watch out for modifying a code signed binary if doing mac app store
• watch out for losing chmod +x permissions
• it might be preferable to make an actual macos binary using a native compiled language to execute things like this to be water tight, but this should work in all cases outside of obscure ones.