Fixing virtualgl for 'vglrun' to work fine and simple, under xproxy (like tigervnc).

svn path=/nixpkgs/trunk/; revision=22586

pkgs/tools/X11/virtualgl/default.nix

@@ -1,5 +1,8 @@
 {stdenv, fetchurl, mesa, libX11, openssl, libXext, libjpeg_turbo}:
 
+let
+  libDir = if stdenv.is64bit then "lib64" else "lib";
+in
 stdenv.mkDerivation {
   name = "virtualgl-2.1.4";
   src = fetchurl {
@@ -9,6 +12,10 @@ stdenv.mkDerivation {
 
   patches = [ ./xshm.patch ];
 
+  prePatch = ''
+    sed -i s,LD_PRELOAD=lib,LD_PRELOAD=$out/${libDir}/lib, rr/vglrun
+  '';
+
   preInstall =''
     export makeFlags="prefix=$out"
   '';