IO#pressed?

static VALUE
console_key_pressed_p(VALUE io, VALUE k)
{
    int vk = -1;

    if (FIXNUM_P(k)) {
        vk = NUM2UINT(k);
    }
    else {
        const struct vktable *t;
        const char *kn;
        if (SYMBOL_P(k)) {
            k = rb_sym2str(k);
            kn = RSTRING_PTR(k);
        }
        else {
            kn = StringValuePtr(k);
        }
        t = console_win32_vk(kn, RSTRING_LEN(k));
        if (!t || (vk = (short)t->vk) == -1) {
            rb_raise(rb_eArgError, "unknown virtual key code: % "PRIsVALUE, k);
        }
    }
    return GetKeyState(vk) & 0x80 ? Qtrue : Qfalse;
}