diff -up xdriinfo-1.0.4/xdriinfo.c~ xdriinfo-1.0.4/xdriinfo.c

--- xdriinfo-1.0.4/xdriinfo.c~	2009-10-16 23:39:10.000000000 +0200

+++ xdriinfo-1.0.4/xdriinfo.c	2017-03-13 12:01:53.419636100 +0100

@@ -101,23 +101,9 @@ int main (int argc, char *argv[]) {

 	    return 1;

 	}

     }

-  /* if the argument to the options command is a driver name, we can handle

-   * it without opening an X connection */

-    if (func == OPTIONS && screenNum == -1) {

-	const char *options = (*GetDriverConfig) (funcArg);

-	if (!options) {

-	    fprintf (stderr,

-		     "Driver \"%s\" is not installed or does not support configuration.\n",

-		     funcArg);

-	    return 1;

-	}

-	printf ("%s", options);

-	if (isatty (STDOUT_FILENO))

-	    printf ("\n");

-	return 0;

-    } 

+

   /* driver command needs a valid screen number */

-    else if (func == DRIVER && screenNum == -1) {

+    if (func == DRIVER && screenNum == -1) {

 	fprintf (stderr, "Invalid screen number \"%s\".\n", funcArg);

 	return 1;

     }

@@ -135,6 +121,9 @@ int main (int argc, char *argv[]) {

 	return 1;

     }

+   /* Call glXGetClientString to load vendor libs on glvnd enabled systems */

+    glXGetClientString (dpy, GLX_EXTENSIONS);

+

     switch (func) {

       case NSCREENS:

 	printf ("%d", nScreens);

@@ -154,7 +143,13 @@ int main (int argc, char *argv[]) {

 	  break;

       }

       case OPTIONS: {

-	  const char *name = (*GetScreenDriver) (dpy, screenNum), *options;

+	  const char *name, *options;

+	  

+	  if (screenNum == -1) {

+	      name = funcArg;

+	  } else {

+	      name = (*GetScreenDriver) (dpy, screenNum);

+	  }

 	  if (!name) {

 	      fprintf (stderr, "Screen \"%d\" is not direct rendering capable.\n",

 		       screenNum);