macOS – Fix ‘Service Cannot Initialize’ Error in Console for plist Files

If a plist is owned by root and writable by a user other than root, that's a security issue.

You can change the owner to root with sudo chown root <filename>, and change the permissions with sudo chmod 644 <filename> (4 for read access, 2 for write access, 1 for execute access, added up. The first number is for the owner, the second for the group, the third for everyone.)

The ultimate problem here is that Bash does not normally kill its non-builtin children.

If bash is waiting for a command to complete and receives a signal for which a
trap has been set, the trap will not be executed until the command completes.
When bash is waiting for an asynchronous command  via  the  wait  builtin, the
reception of a signal for which a trap has been set will cause the wait builtin
to return immediately with an exit status greater than 128, immediately after
which  the trap is executed.

When you hit <CTRL>+<C> you're killing the shell script, which behaves normally -- but the sleep lives on. Use ps to see.

When try to stop things externally, via kill, then Bash as above. After some time-out period (I'm guessing 20 seconds) launchd then issues a kill -9 which the script cannot trap.

The solution is to issue a wait after the sleep, to indicate to Bash that it can interrupt itself:

sleep 86400 & wait

This will allow the script to be interrupted, but the sleep will still survive. I'm sure there's a way to kill the children, but I didn't bother looking it up...