On Fri, Sep 27, 2019 at 03:28:39PM +0200, Sebastian Sareyko wrote:
> Doing a multi-head setup using other means than Xinerama may lead to
> XineramaQueryScreens() returning the screens in an order that does not
> actually represent the actual screen layout. This in turn may result
> in dwm using the "wrong" monitor in monitor related
> functions (focusmon(), tagmon(), applying rules, ...).
>
> This change sorts the list of unique screens by their horizontal
> origin to alleviate this problem.
> The change does not solve (and may even provoke) the described issue
> when screens are not only placed next to each other in a horizontal
> way but also vertically.
> ---
> dwm.c | 19 +++++++++++++++++++
> 1 file changed, 19 insertions(+)
>
> diff --git a/dwm.c b/dwm.c
> index 4465af1..a8e9467 100644
> --- a/dwm.c
> +++ b/dwm.c
> @@ -1847,6 +1847,24 @@ updateclientlist()
> (unsigned char *) &(c->win), 1);
> }
>
> +#ifdef XINERAMA
> +void
> +sortscreens(XineramaScreenInfo *screens, int n)
> +{
> + int i, j;
> + XineramaScreenInfo *screen = ecalloc(1, sizeof(XineramaScreenInfo));
> +
> + for (i = 0; i < n; i++)
> + for (j = i + 1; j < n; j++)
> + if (screens[i].x_org > screens[j].x_org) {
> + memcpy(&screen[0], &screens[i],
> sizeof(XineramaScreenInfo));
> + memcpy(&screens[i], &screens[j],
> sizeof(XineramaScreenInfo));
> + memcpy(&screens[j], &screen[0],
> sizeof(XineramaScreenInfo));
> + }
> + XFree(screen);
> +}
> +#endif /* XINERAMA */
> +
> int
> updategeom(void)
> {
> @@ -1868,6 +1886,7 @@ updategeom(void)
> memcpy(&unique[j++], &info[i],
> sizeof(XineramaScreenInfo));
> XFree(info);
> nn = j;
> + sortscreens(unique, nn);
> if (n <= nn) { /* new monitors available */
> for (i = 0; i < (nn - n); i++) {
> for (m = mons; m && m->next; m = m->next);
> --
> 2.21.0
>
>
Have you tried xrandr to reorder the screens? It should probably be solved in a
different way.
--
Kind regards,
Hiltjo
