For script build_documentation.sh impelemented the command line parsing for...

function declare_global_variables {

    declare -g publish_mode

    declare -g doc_top_level

}

#-----------------------------------------------------

    help_frmt1='%-72s %-72s\n'

    frmtmodes='%-72s \t%-72s\n'

    printf "Usage:\n"

    printf "\tbuild_documentation.sh [ -h | --help ] --publish-dir <PUBLISHDIR> --doc-top-level <DOCTOPLEVEL>\n\n"

    printf "\tbuild_documentation.sh [ -h | --help ] --publish-mode <PUBLISHMODE> --doc-top-level <DOCTOPLEVEL>\n\n"

    printf "${help_frmt1}" "option" "description"

    for ip in {1..145};do

        printf "%s" "-"

            --doc-top-level)

                doc_top_level=${2}

                doc_top_level=$(realpath ${doc_top_level})

                shift 2;;

            -- ) 

#

# Positional parameters:

#   ${1} The location of the documentation top level. 

#   ${2} The location to publish the documentation.

#   ${2} The publish mode

# ----------------------------------------------------

function publish_documentation {

    echo "Executing function publish_documentation"

    local -r my_doc_top_level=${1}

    local -r my_publish_dir=${2}  

    local -r my_publish_mode=${2}  

    local -r my_start_dir=$(pwd)

    cd ${doc_top_level}

    echo "doc_top_level = ${my_doc_top_level}"

    echo "my_publish_mode = ${my_publish_mode}"

    # PUBLISHDIR=${my_publish_dir} make clean && PUBLISHDIR=${my_publish_dir} make html 

    cd ${my_start_dir}

    fi

    # We now publish the documentation.

    publish_documentation "${doc_top_level}" "${publish_dir}"

    publish_documentation "${doc_top_level}" "${publish_mode}"

}

# ----------------------------------------------------

#