Using `set -u` is more portable. If your shebang is `/usr/bin/env bash`, which it probably should be, then you can't add additional command line arguments in Li

Using `set -u` is more portable. If your shebang is `/usr/bin/env bash`, which it probably should be, then you can't add additional command line arguments in Linux with older coreutils. macOS supports additional arguments, regardless, and in Linux, coreutils 8.30 added the `-S` option to `env` to get around this problem.