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Bash Scripting Patterns and Practical Recipes/Parse flags with while/case

Implement manual flag parsing in Bash.

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Section: Script Structure

Parse flags with while/case

bash
bash
while (($#)); do
  case "$1" in
    -v|--verbose) verbose=1 ;;
    -o|--output) output=$2; shift ;;
    *) echo "unknown arg: $1" >&2; exit 1 ;;
  esac
  shift
done
Explanation

A common pattern for lightweight scripts.

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