mjhjmtu

When using getopts with case clause, is a *) pattern subclause as the last pattern subclause equivalent to the union of ?) and :) pattern subclauses as the last two pattern subclauses? Specifically,

while getopts "<optionString>" opt; do
 case $opt in
 a) a="$OPTARG"
 ;;
 b) b="$OPTARG"
 ;;

 ...
 ;;

 ?) printf "illegal option: -%sn" "$OPTARG" >&2
 exit 1
 ;;
 :) printf "missing argument for -%sn" "$OPTARG" >&2
 exit 1
 ;;
 esac
done

and

while getopts "<optionString>" opt; do
 case $opt in
 a) a="$OPTARG"
 ;;
 b) b="$OPTARG"
 ;;

 ...
 ;;

 *) printf "illegal option: -%s, or missing argument for -%sn" "$OPTARG" "$OPTARG" >&2
 exit 1
 ;;
 esac
done

Thanks.

You only really need to check for : and ? with the getopts in bash if you use silent error reporting (when the first character of the optstring is a colon).

When getopts in not used in that way, it will produce its own diagnostic messages for invalid options and for missing option arguments (and these are usually quite adequate). In fact, it will not place : or ? in the variable unless it's silenced.

Using * in a case statement would be a way to catch both of these, but if getopts is silenced, you would not know which error was triggered and would just be able to say something on the lines of an error occurred while parsing the command line options to the user.