The reason for this is that the macOS version uses a deprecated API and in order to correct this, the file needs to be compiled as Objective-C++ which requires a different extension.
This cuts down on as much message noise as possible, outputs everything to a file specified as a parameter and then quits immediately, allowing this to run from a batch that's supposed to check a larger list of files for errors.
Multiple outputs get appended if the file already exists.
Root permissions are required to be able to create directories inside /Library/Application Support
So user's ~/Library/Application Support is used to store cached nodes
- If the current user does not have write permissions for the directory
zdoom.exe is located in, use standard folder paths located in their home
directory instead. This is a common scenario when people put ZDoom into
Program Files. (Ironically, zdoom.ini used to be in AppData, buth then
people complained when it wasn't in the same directory as zdoom.exe, so
it got turned into zdoom-<user>.ini so at least it could retain some
multi-user support. I'm not sure when the AppData support was removed,
though, since it should have still been kept around for migrating
configs to the new name.)