WIP wrapper function for capturing stderr/stdout/rc to vars + optionally printing stdout/stderr

#!/bin/bash

function simpleTest() {
    printf '%s\n' 'This should appear on stderr' >&2;
    printf '%s\n' 'This should appear on stdout';
    return 42
}

function simpleColorTest() {
    local red="$(tput setaf 1)";
    local green="$(tput setaf 2)";
    local magenta="$(tput setaf 5)";
    local cyan="$(tput setaf 6)"
    local normal="$(tput sgr0)";
    printf '%s\n' "${red}ERROR:${normal} This should appear on ${magenta}stderr${normal}" >&2;
    printf '%s\n' "${green}PASS:${normal} This should appear on ${cyan}stdout${normal}";
    return 42
}

function realTimeStdoutTest() {
    # simulate realtime output on stdout, similar to what you might get from
    #   traceroute reddit.com
    # but faster and with less dependencies
    local i n=5;
    for(( i=1; i <= n; i++)); do
        sleep 0.5s;
        printf '%s\n' "stdout $i of $n";
    done
    return 33
}

function realTimeColoredStdoutTest() {
    # simulate realtime output on stdout, similar to what you might get from
    #   traceroute reddit.com
    # but faster and with less dependencies
    local red="$(tput setaf 1)";
    local green="$(tput setaf 2)";
    local magenta="$(tput setaf 5)";
    local cyan="$(tput setaf 6)"
    local normal="$(tput sgr0)";
    local i n=5;
    for(( i=1; i <= n; i++)); do
        sleep 0.5s;
        printf '%s\n' "${cyan}stdout${normal} ${green}${i}${normal} of ${magenta}${n}${normal}";
    done
    return 33
}

function realTimeStderrTest() {
    # simulate realtime output on stderr, similar to what you might get from
    #   curl --no-clobber -L -A "${userAgent}" "${url}" -O "${fileName}"
    # but faster and with less dependencies
    local i n=5;
    for(( i=1; i <= n; i++)); do
        sleep 0.5s;
        printf '%s\n' "stderr $i of $n" >&2;
    done
    return 55
}

function realTimeColoredStderrTest() {
    # simulate realtime output on stderr, similar to what you might get from
    #   curl --no-clobber -L -A "${userAgent}" "${url}" -O "${fileName}"
    # but faster and with less dependencies
    local red="$(tput setaf 1)";
    local green="$(tput setaf 2)";
    local magenta="$(tput setaf 5)";
    local cyan="$(tput setaf 6)"
    local normal="$(tput sgr0)";
    local i n=5;
    for(( i=1; i <= n; i++)); do
        sleep 0.5s;
        printf '%s\n' "stderr $i of $n" >&2;
        printf '%s\n' "${red}stderr${normal} ${green}${i}${normal} of ${magenta}${n}${normal}";
    done
    return 55
}

print_read() {
    local LANG=C IFS REPLY;
    while read -r -d ''; do
        printf "${1}\0%s\0" "$REPLY";
    done
    printf "${1}\0%s\0" "$REPLY";
}

function wrapper() {
    local code REPLY;
    # TODO: also pass var names for exporting so caller
    # can grab these. for now, just capture locally
    local outstr errstr rc;

    # TODO: set these from passed options. for now, just hard-code
    local printStderr=0 printStdout=0;

    if [[ '-O' == "$1" ]]; then
        echo "printStdout=1"
        printStdout=1;
        shift 1;
        exec 5>&1
    fi
    if [[ '-E' == "$1" ]]; then
        echo "PrintStderr=1"
        printStderr=1
        shift 1;
        exec 6>&2
    fi

    echo ""
    echo "======================================="
    echo "realtime output"
    echo "======================================="

    {
        while IFS= read -r -d '' code; do
            IFS= read -r -d ''
            case "$code" in
                '1') outstr+="$REPLY"
                ;;
                '2') errstr+="$REPLY"
                ;;
                'e') rc="$REPLY" ;;
                *)
                    #printf '%s\n' 'A dev broke this script' 1>&2
                    exit 1
                ;;
            esac
        done
    } < <(
        {
            "${@}" 1> >(
                if [[ 1 == "$printStdout" ]]; then
                    tee >(cat - >&5) | print_read '1'
                else
                    print_read '1'
                fi
            )
            printf "e\0%d\0" "$?"
        } 2> >(
            if [[ 1 == "$printStderr" ]]; then
                tee >(cat - >&6) | print_read '2'
            else
                print_read '2'
            fi
        )
    )

    echo ""
    echo "======================================="
    echo "captured variables"
    echo "======================================="
    echo "rc: ${rc}";
    echo "errstr: ";
    echo "${errstr}";
    echo ""
    echo "outstr: ";
    echo "${outstr}";
    echo ""
}