bash_howto_getopts.sh

#!/bin/bash

while getopts a:bc: flag; do
  case $flag in
    a)
      opt_a=$OPTARG
      ;;
    b)
      opt_b=1
      ;;
    c)
      opt_c=$OPTARG
      ;;
    ?)
      echo "usage: ...."
      exit 1
      ;;
  esac
done

shift $(( OPTIND - 1 ));

echo $*

##
## bash -x ~/work/bash_test/test_getopts.sh -a 1 -b -c a arg1 arg2 result below
+ getopts a:bc: flag
+ case $flag in
+ opt_a=1
+ getopts a:bc: flag
+ case $flag in
+ opt_b=1
+ getopts a:bc: flag
+ case $flag in
+ opt_c=a
+ getopts a:bc: flag
+ shift 5
+ echo arg1 arg2
arg1 arg2