detectos.sh

function cache_uname {
    what=$(uname -srm)
    read -ra uname <<< "$what"

    kern_name="${uname[0]}"
    kern_vers="${uname[1]}"
    mach_arch="${uname[2]}"
}

function get_os {
    case "$kern_name" in
        "Linux") os="linux" ;;
        "Darwin") os="darwin" ;;
        *"BSD" | "DragonFly" | "Bitrig") os="bsd" ;;
        "CYGWIN"*) os="win" ;;
        "SunOS") os="solaris" ;;
        "Haiku") os="haiku" ;;
        "GNU"*) os="gnu" ;;
        *) printf "%s\n" "unkwown: $kern_name"; exit 1 ;;
    esac
}

cache_uname
get_os

echo "$kern_name"
echo "$kern_vers"
echo "$mach_arch"
echo "$os"