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Defaulted and Required Parameters

Bash & Scripting · medium · solved in-browser (no VM needed) · 3 tiered hints

Write /home/player/run.sh (shebang #!/bin/bash) that uses parameter expansion to configure itself from the environment. Give PORT a fallback with ${PORT:-8080}, and make HOST mandatory with ${HOST:?...} so the script aborts with a message if HOST is unset or empty. (Authored config, graded structurally — the engine isn't run here.)

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