/* default hpgl prologue */
_hpprodf(mode, auto, userstr)
{
        local def;

        if (argc < 3)
        {
                if (argc < 2)
                {
                        if (argc < 1) mode = castint(getconf("HPGL_HPGL2")) > 0;
                        auto = 1;
                }
                userstr = "";
        }

        def = (mode) ? getconf("HPGL_PROLOGUE2") : getconf("HPGL_PROLOGUE1");

        if (not(auto))
        {
                def = userstr;
        }
        return(def);
}