Bash Example for Parsing Command Line Arguments

parsecli.sh

#!/bin/bash
#
# A simple example of how to parse CLI options and arguments

## === variable Declarations
# Script name without any directories ("basename"):
PROG=${0##*/}

# Version information:
VERSION="1.0.0"

# Verbosity level:
VERBOSE=0

# Arguments, the rest after parsing all options:
ARGS=""


## === Functions

function usage() {
  cat << EOF
SYNOPSIS
   $PROG [-v]...
   $PROG --version
   $PROG -h|--help
   $PROG 

OPTIONS
   -v, -vv, -vvv..   Raise verbosity level
   -h, --help        Display this help and exit
   --version         Output version information and exit
EOF
}

function parsecli()
{
    # For details about getopt,
    # see https://www.tutorialspoint.com/unix_commands/getopt.htm
    local options=$(getopt -n "$PROG" -o v,h -l version,help -- "$@")
    [ $? -eq 0 ] || {
        echo "Incorrect option provided"
        exit 1
    }
    eval set -- "$options"
    while true; do
        case "$1" in
        -v)
            VERBOSE=$(($VERBOSE + 1))
            ;;
        -h|--help)
            usage
            ;;
        --version)
            echo "$PROG $VERSION"
            exit
            ;;
        --)
            shift
            break
            ;;
        esac
        shift
    done
    # Remove script name:
    shift
    ARGS="$@"
}

parsecli $0 "$@"

echo "VERBOSE=$VERBOSE"
echo "ARGS=$ARGS"