How can I use long options with the Bash getopts builtin?

Question

I am trying to parse a -temp option with Bash getopts. I\'m calling my script like this:

./myscript -temp /foo/bar/someFile

He

Answer 1

the simplest way to achieve this is with the help of getopt and --longoptions

try this , hope this is useful

# Read command line options
ARGUMENT_LIST=(
    "input1"
    "input2"
    "input3"
)



# read arguments
opts=$(getopt \
    --longoptions "$(printf "%s:," "${ARGUMENT_LIST[@]}")" \
    --name "$(basename "$0")" \
    --options "" \
    -- "$@"
)


echo $opts

eval set --$opts

while true; do
    case "$1" in
    --input1)  
        shift
        empId=$1
        ;;
    --input2)  
        shift
        fromDate=$1
        ;;
    --input3)  
        shift
        toDate=$1
        ;;
      --)
        shift
        break
        ;;
    esac
    shift
done

and this is how - you call the shell script

myscript.sh --input1 "ABC" --input2 "PQR" --input2 "XYZ"

Answer 2

getopts can only parse short options.

Most systems also have an external getopt command, but getopt is not standard, and is generally broken by design as it can't handle all arguments safely (arguments with whitespace and empty arguments), only GNU getopt can handle them safely, but only if you use it in a GNU-specific way.

The easier choice is to use neither, just iterate the script's arguments with a while-loop and do the parsing yourself.

See http://mywiki.wooledge.org/BashFAQ/035 for an example.

Answer 3

getopts is used by shell procedures to parse positional parameters of 1 character only (no GNU-style long options (--myoption) or XF86-style long options (-myoption))