How can i read flags after positional arguments in bash script

Question

How can I able to read the flags after the positional arguments.

echo $1
echo $2
while getopts "j:" opt; do
    echo $opt $OPTIND $OPTARG
done
$ bash test.sh arg1 arg2 -f flag1
// out: arg1
        arg2

Not able to get the flag. But if i place the flag argument before the positional then im able to get the flag and its arg

score 0 · Answer 1 · answered May 08 '22 at 19:25

0

$ cat test.sh
#!/usr/bin/env bash

echo "$1"
echo "$2"
shift 2
while getopts "f:" opt; do
    echo "$opt $OPTIND $OPTARG"
done

$ bash test.sh arg1 arg2 -f flag1
arg1
arg2
f 3 flag1

answered May 08 '22 at 19:25

Ed Morton

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score 0 · Answer 2 · answered May 08 '22 at 20:43

GNU getopt handles this

$ set -- arg1 arg2 -f flag1
$ getopt -o f: -- "$@"
 -f 'flag1' -- 'arg1' 'arg2'

The way to iterate over the args is modelled in the getopt-example.bash

args=$(getopt -o 'f:' -n 'myprog.bash' -- "$@") || {
    echo 'Terminating...' >&2
    exit 1
}

eval set -- "$args"

while true; do
    case "$1" in
        '-f')
            flag=$2
            shift 2
            ;;
        '--')
            shift
            break
            ;;
        *)  echo "error: $1" >&2
            exit 1
            ;;
    esac
done

# remaining args are in "$@"

How can i read flags after positional arguments in bash script

2 Answers2