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bashpositional-operator

Bash: handling mass arguments

I'd like to be able to handle multiple arguments to a given flag no matter what the order of flags is. Do you guys think this is acceptable? Any improvements?

So: 

$ ./script -c opt1 opt2 opt3 -b foo

opt1 opt2 opt3
foo

Code:

echo_args () {
    echo "$@"
}


while (( $# > 0 )); do
    case "$1" in
        -b)
            echo $2
        ;;

        -c|--create)
            c_args=()

            # start looping from this flag
            for arg in ${@:2}; do
                [ "${arg:0:1}" == "-" ] && break
                c_args+=("$arg")
            done

            echo_args "${c_args[@]}"
        ;;

        *)
            echo "huh?"
        ;;
    esac

    shift 1
done
Solution

  • The getopts utility shall retrieve options and option-arguments from a list of parameters.

    $ cat script.sh

cflag=
bflag=
while getopts c:b: name
do
    case $name in
    b)    bflag=1
          bval="$OPTARG";;
    c)    cflag=1
          cval="$OPTARG";;
    ?)   printf "Usage: %s: [-c value] [-b value] args\n" $0
          exit 2;;
    esac
done
if [ ! -z "$bflag" ]; then
    printf 'Option -b "%s" specified\n' "$bval"
fi
if [ ! -z "$cflag" ]; then
    printf 'Option -c "%s" specified\n' "$cval"
fi
shift $(($OPTIND - 1))
printf "Remaining arguments are: %s\n" "$*"

    Note the Guideline 8: When multiple option-arguments are specified to follow a single option, they should be presented as a single argument, using commas within that argument or <blank>s within that argument to separate them.

    $ ./script.sh -c "opt1 opt2 opt3" -b foo

Option -b "foo" specified
Option -c "opt1 opt2 opt3" specified
Remaining arguments are:

    The standard links are listed below: