shell script respond to keypress

Question

I have a shell script that essentially says something like

while true; do
    read -r input
    if [\"$input\" = \"a\"]; then 
        echo \"hello world\"          


        

Answer 1

I have a way to do this in my project: https://sourceforge.net/p/playshell/code/ci/master/tree/source/keys.sh

It reads a single key everytime key_readonce is called. For special keys, a special parsing loop would run to also be able to parse them.

This is the crucial part of it:

if read -rn 1 -d '' "${T[@]}" "${S[@]}" K; then
    KEY[0]=$K

    if [[ $K == $'\e' ]]; then
        if [[ BASH_VERSINFO -ge 4 ]]; then
            T=(-t 0.05)
        else
            T=(-t 1)
        fi

        if read -rn 1 -d '' "${T[@]}" "${S[@]}" K; then
            case "$K" in
            \[)
                KEY[1]=$K

                local -i I=2

                while
                    read -rn 1 -d '' "${T[@]}" "${S[@]}" "KEY[$I]" && \
                    [[ ${KEY[I]} != [[:upper:]~] ]]
                do
                    (( ++I ))
                done
                ;;
            O)
                KEY[1]=$K
                read -rn 1 -d '' "${T[@]}" 'KEY[2]'
                ;;
            [[:print:]]|$'\t'|$'\e')
                KEY[1]=$K
                ;;
            *)
                __V1=$K
                ;;
            esac
        fi
    fi

    utils_implode KEY __V0