diff --git a/ChangeLog b/ChangeLog
index 3e0a3f16..21d343a4 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,12 @@
+2000-11-27  Martin Baulig  <martin@home-of-linux.org>
+
+	* include/glibtop/glibtop-backend-info.h
+	(glibtop_backend_close_func_t): Added `void *closure' argument.
+
+	* include/glibtop/call-vector.h: Changed the second argument
+	of all function in the call vector from `glibtop_backend *' to
+	`void *closure'.
+
 2000-11-26  Martin Baulig  <martin@home-of-linux.org>
 
 	* include/glibtop/glibtop-backend.h (glibtop_backend_open):
diff --git a/backends/common/backend-common.c b/backends/common/backend-common.c
index 3cea9d28..840f3ee1 100644
--- a/backends/common/backend-common.c
+++ b/backends/common/backend-common.c
@@ -29,7 +29,7 @@ static int
 _open_common (glibtop_server *, glibtop_backend *, u_int64_t, const char **);
 
 static int
-_close_common (glibtop_server *, glibtop_backend *);
+_close_common (glibtop_server *, glibtop_backend *, void *closure);
 
 extern glibtop_call_vector glibtop_backend_common_call_vector;
 
@@ -53,8 +53,9 @@ _open_common (glibtop_server *server, glibtop_backend *backend,
 }
 
 static int
-_close_common (glibtop_server *server, glibtop_backend *backend)
+_close_common (glibtop_server *server, glibtop_backend *backend,
+	       void *closure)
 {
-    return -1;
+    return 0;
 }
 
diff --git a/backends/common/marshal.pl b/backends/common/marshal.pl
index 545a6a09..54349023 100644
--- a/backends/common/marshal.pl
+++ b/backends/common/marshal.pl
@@ -137,16 +137,16 @@ sub output {
 
     $func_decl = 'static '.$retval."\n";
     if ($line_fields[3] eq '') {
-      $func_decl .= sprintf ("_glibtop_get_%s_c (glibtop_server *server, glibtop_backend *backend%s)\n",
+      $func_decl .= sprintf ("_glibtop_get_%s_c (glibtop_server *server, void *closure%s)\n",
 			     $feature, $param_decl);
     } elsif ($line_fields[3] eq 'array') {
-      $func_decl .= sprintf ("_glibtop_get_%s_c (glibtop_server *server, glibtop_backend *backend, glibtop_array *array%s)\n",
+      $func_decl .= sprintf ("_glibtop_get_%s_c (glibtop_server *server, void *closure, glibtop_array *array%s)\n",
 			     $feature, $param_decl);
     } elsif ($line_fields[3] =~ /^array/) {
-      $func_decl .= sprintf ("_glibtop_get_%s_c (glibtop_server *server, glibtop_backend *backend, glibtop_array *array, %s *buf%s)\n",
+      $func_decl .= sprintf ("_glibtop_get_%s_c (glibtop_server *server, void *closure, glibtop_array *array, %s *buf%s)\n",
 			     $feature, 'glibtop_'.$feature, $param_decl);
     } else {
-      $func_decl .= sprintf ("_glibtop_get_%s_c (glibtop_server *server, glibtop_backend *backend, %s *buf%s)\n",
+      $func_decl .= sprintf ("_glibtop_get_%s_c (glibtop_server *server, void *closure, %s *buf%s)\n",
 			     $feature, 'glibtop_'.$feature, $param_decl);
     }
 
diff --git a/backends/server/backend-server.c b/backends/server/backend-server.c
index 625820d1..743e62e4 100644
--- a/backends/server/backend-server.c
+++ b/backends/server/backend-server.c
@@ -29,10 +29,7 @@ static int
 _open_server (glibtop_server *, glibtop_backend *, u_int64_t, const char **);
 
 static int
-_close_server (glibtop_server *, glibtop_backend *);
-
-static int backend_server_initialized = 0;
-GQuark backend_server_quark;
+_close_server (glibtop_server *, glibtop_backend *, void *);
 
 extern glibtop_call_vector glibtop_backend_server_call_vector;
 
@@ -54,15 +51,9 @@ _open_server (glibtop_server *server, glibtop_backend *backend,
 {
     backend_server_private *priv;
 
-    if (!backend_server_initialized) {
-	backend_server_quark = g_quark_from_string ("backend-server-private");
-
-	backend_server_initialized = 1;
-    }
-
     priv = glibtop_calloc_r (server, 1, sizeof (backend_server_private));
 
-    g_object_set_qdata (G_OBJECT (backend), backend_server_quark, priv);
+    glibtop_backend_set_closure_data (backend, priv);
 
 #ifdef DEBUG
     fprintf (stderr, "open_server - %p, %p, %p\n", server, backend, priv);
@@ -102,12 +93,10 @@ _open_server (glibtop_server *server, glibtop_backend *backend,
 }
 
 static int
-_close_server (glibtop_server *server, glibtop_backend *backend)
+_close_server (glibtop_server *server, glibtop_backend *backend,
+	       void *closure)
 {
-    backend_server_private *priv;
-
-    priv = g_object_steal_qdata (G_OBJECT (backend), backend_server_quark);
-    g_assert (priv != NULL);
+    backend_server_private *priv = closure;
 
     kill (priv->pid, SIGKILL);
     close (priv->input [0]);
diff --git a/backends/server/backend-server.h b/backends/server/backend-server.h
index c0fd0024..636519d1 100644
--- a/backends/server/backend-server.h
+++ b/backends/server/backend-server.h
@@ -46,10 +46,8 @@ struct _backend_server_private
     glibtop_server *server;
 };
 
-extern GQuark backend_server_quark;
-
 void *
-glibtop_call_i (glibtop_server *server, glibtop_backend *backend,
+glibtop_call_i (glibtop_server *server, backend_server_private *priv,
 		unsigned command, size_t send_size, const void *send_ptr,
 		size_t data_size, const void *data_ptr,
 		size_t recv_size, void *recv_ptr,
diff --git a/backends/server/command.c b/backends/server/command.c
index ee6053d9..1821b938 100644
--- a/backends/server/command.c
+++ b/backends/server/command.c
@@ -28,7 +28,7 @@
 #include "command.h"
 
 void *
-glibtop_call_i (glibtop_server *server, glibtop_backend *backend,
+glibtop_call_i (glibtop_server *server, backend_server_private *priv,
 		unsigned command, size_t send_size, const void *send_buf,
 		size_t data_size, const void *data_buf,
 		size_t recv_size, void *recv_ptr,
@@ -36,7 +36,6 @@ glibtop_call_i (glibtop_server *server, glibtop_backend *backend,
 {
     glibtop_command cmnd;
     glibtop_response resp;
-    backend_server_private *priv;
 #if 0
     int retval;
 #endif
@@ -44,9 +43,6 @@ glibtop_call_i (glibtop_server *server, glibtop_backend *backend,
     memset (&cmnd, 0, sizeof (glibtop_command));
     memset (&resp, 0, sizeof (glibtop_response));
 
-    priv = g_object_get_qdata (G_OBJECT (backend), backend_server_quark);
-    g_assert (priv != NULL);
-
     cmnd.command = command;
 
     /* If send_size is less than _GLIBTOP_PARAM_SIZE (normally 16 Bytes), we
diff --git a/backends/server/marshal.pl b/backends/server/marshal.pl
index 3fc29d40..d00dc5e9 100644
--- a/backends/server/marshal.pl
+++ b/backends/server/marshal.pl
@@ -198,7 +198,7 @@ sub output {
     $send_buf_code .= "\t_LIBGTOP_DATA_ptr = _LIBGTOP_DATA_buf;\n";
 
     $call_code = '';
-    $call_code .= sprintf ("\t%sglibtop_call_i (server, backend, GLIBTOP_CMND_%s,\n",
+    $call_code .= sprintf ("\t%sglibtop_call_i (server, closure, GLIBTOP_CMND_%s,\n",
 			   $call_prefix, &toupper($feature));
     $call_code .= sprintf ("\t\t\t%s%s, %s,\n", $call_prefix_space,
 			   "_LIBGTOP_SEND_len", "_LIBGTOP_SEND_buf");
@@ -257,16 +257,16 @@ sub output {
 
     $func_decl = 'static '.$retval."\n";
     if ($line_fields[3] eq '') {
-      $func_decl .= sprintf ("_glibtop_get_%s_c (glibtop_server *server, glibtop_backend *backend%s)\n",
+      $func_decl .= sprintf ("_glibtop_get_%s_c (glibtop_server *server, void *closure%s)\n",
 			     $feature, $param_decl);
     } elsif ($line_fields[3] eq 'array') {
-      $func_decl .= sprintf ("_glibtop_get_%s_c (glibtop_server *server, glibtop_backend *backend, glibtop_array *array%s)\n",
+      $func_decl .= sprintf ("_glibtop_get_%s_c (glibtop_server *server, void *closure, glibtop_array *array%s)\n",
 			     $feature, $param_decl);
     } elsif ($line_fields[3] =~ /^array/) {
-      $func_decl .= sprintf ("_glibtop_get_%s_c (glibtop_server *server, glibtop_backend *backend, glibtop_array *array, %s *buf%s)\n",
+      $func_decl .= sprintf ("_glibtop_get_%s_c (glibtop_server *server, void *closure, glibtop_array *array, %s *buf%s)\n",
 			     $feature, 'glibtop_'.$feature, $param_decl);
     } else {
-      $func_decl .= sprintf ("_glibtop_get_%s_c (glibtop_server *server, glibtop_backend *backend, %s *buf%s)\n",
+      $func_decl .= sprintf ("_glibtop_get_%s_c (glibtop_server *server, void *closure, %s *buf%s)\n",
 			     $feature, 'glibtop_'.$feature, $param_decl);
     }
 
diff --git a/backends/sysdeps/backend-sysdeps.c b/backends/sysdeps/backend-sysdeps.c
index 70d273c5..e7e98c71 100644
--- a/backends/sysdeps/backend-sysdeps.c
+++ b/backends/sysdeps/backend-sysdeps.c
@@ -29,7 +29,7 @@ static int
 _open_sysdeps (glibtop_server *, glibtop_backend *, u_int64_t, const char **);
 
 static int
-_close_sysdeps (glibtop_server *, glibtop_backend *);
+_close_sysdeps (glibtop_server *, glibtop_backend *, void *);
 
 extern glibtop_call_vector glibtop_backend_sysdeps_call_vector;
 
@@ -68,8 +68,9 @@ _open_sysdeps (glibtop_server *server, glibtop_backend *backend,
 }
 
 static int
-_close_sysdeps (glibtop_server *server, glibtop_backend *backend)
+_close_sysdeps (glibtop_server *server, glibtop_backend *backend,
+		void *closure)
 {
-    return -1;
+    return 0;
 }
 
diff --git a/backends/sysdeps/marshal.pl b/backends/sysdeps/marshal.pl
index 132581b9..4ccf94f5 100644
--- a/backends/sysdeps/marshal.pl
+++ b/backends/sysdeps/marshal.pl
@@ -137,16 +137,16 @@ sub output {
 
     $func_decl = 'static '.$retval."\n";
     if ($line_fields[3] eq '') {
-      $func_decl .= sprintf ("_glibtop_get_%s_c (glibtop_server *server, glibtop_backend *backend%s)\n",
+      $func_decl .= sprintf ("_glibtop_get_%s_c (glibtop_server *server, void *closure%s)\n",
 			     $feature, $param_decl);
     } elsif ($line_fields[3] eq 'array') {
-      $func_decl .= sprintf ("_glibtop_get_%s_c (glibtop_server *server, glibtop_backend *backend, glibtop_array *array%s)\n",
+      $func_decl .= sprintf ("_glibtop_get_%s_c (glibtop_server *server, void *closure, glibtop_array *array%s)\n",
 			     $feature, $param_decl);
     } elsif ($line_fields[3] =~ /^array/) {
-      $func_decl .= sprintf ("_glibtop_get_%s_c (glibtop_server *server, glibtop_backend *backend, glibtop_array *array, %s *buf%s)\n",
+      $func_decl .= sprintf ("_glibtop_get_%s_c (glibtop_server *server, void *closure, glibtop_array *array, %s *buf%s)\n",
 			     $feature, 'glibtop_'.$feature, $param_decl);
     } else {
-      $func_decl .= sprintf ("_glibtop_get_%s_c (glibtop_server *server, glibtop_backend *backend, %s *buf%s)\n",
+      $func_decl .= sprintf ("_glibtop_get_%s_c (glibtop_server *server, void *closure, %s *buf%s)\n",
 			     $feature, 'glibtop_'.$feature, $param_decl);
     }
 
diff --git a/include/glibtop/call-vector.h.in b/include/glibtop/call-vector.h.in
index b1ab81dd..8c02d478 100644
--- a/include/glibtop/call-vector.h.in
+++ b/include/glibtop/call-vector.h.in
@@ -31,8 +31,6 @@
 #include <glibtop.h>
 #include <glibtop/union.h>
 
-#include <glibtop/backend.h>
-
 BEGIN_LIBGTOP_DECLS
 
 struct _glibtop_call_vector
diff --git a/include/glibtop/call-vector.pl b/include/glibtop/call-vector.pl
index 53b16077..ad6a6514 100644
--- a/include/glibtop/call-vector.pl
+++ b/include/glibtop/call-vector.pl
@@ -82,16 +82,16 @@ sub parse_features_def {
 
   if ($line_fields[3] eq '') {
     $func_decl_code .= sprintf
-      (qq[\t%s (*%s) (glibtop_server *, glibtop_backend *%s);\n], $retval, $feature, $param_decl);
+      (qq[\t%s (*%s) (glibtop_server *, void *%s);\n], $retval, $feature, $param_decl);
   } elsif ($line_fields[3] eq 'array') {
     $func_decl_code .= sprintf
-      (qq[\t%s (*%s) (glibtop_server *, glibtop_backend *, glibtop_array *%s);\n], $retval, $feature, $param_decl);
+      (qq[\t%s (*%s) (glibtop_server *, void *, glibtop_array *%s);\n], $retval, $feature, $param_decl);
   } elsif ($line_fields[3] =~ /^array/) {
     $func_decl_code .= sprintf
-      (qq[\t%s (*%s) (glibtop_server *, glibtop_backend *, glibtop_array *, %s *%s);\n], $retval, $feature, 'glibtop_'.$feature, $param_decl);
+      (qq[\t%s (*%s) (glibtop_server *, void *, glibtop_array *, %s *%s);\n], $retval, $feature, 'glibtop_'.$feature, $param_decl);
   } else {
     $func_decl_code .= sprintf
-      (qq[\t%s (*%s) (glibtop_server *, glibtop_backend *, %s *%s);\n], $retval, $feature, 'glibtop_'.$feature, $param_decl);
+      (qq[\t%s (*%s) (glibtop_server *, void *, %s *%s);\n], $retval, $feature, 'glibtop_'.$feature, $param_decl);
   }
 }
 
diff --git a/include/glibtop/glibtop-backend-info.h b/include/glibtop/glibtop-backend-info.h
index 3c25fb1c..8387d1a9 100644
--- a/include/glibtop/glibtop-backend-info.h
+++ b/include/glibtop/glibtop-backend-info.h
@@ -39,9 +39,10 @@ typedef struct _glibtop_backend_module	glibtop_backend_module;
 
 typedef struct _glibtop_call_vector	glibtop_call_vector;
 
-typedef int (*glibtop_backend_open_func_t) (glibtop_server *, glibtop_backend *,
-					    u_int64_t, const char **);
-typedef int (*glibtop_backend_close_func_t) (glibtop_server *, glibtop_backend *);
+typedef int (*glibtop_backend_open_func_t)  (glibtop_server *, glibtop_backend *,
+					     u_int64_t, const char **);
+typedef int (*glibtop_backend_close_func_t) (glibtop_server *, glibtop_backend *,
+					     void *);
 
 struct _glibtop_backend_info
 {
diff --git a/include/glibtop/glibtop-backend.h b/include/glibtop/glibtop-backend.h
index 816df427..24f4e837 100644
--- a/include/glibtop/glibtop-backend.h
+++ b/include/glibtop/glibtop-backend.h
@@ -68,6 +68,12 @@ glibtop_backend *
 glibtop_backend_get (const char *backend_name, u_int64_t features,
 		     const char **backend_args, GError **error);
 
+void
+glibtop_backend_set_closure_data (glibtop_backend *backend, void *closure);
+
+void *
+glibtop_backend_get_closure_data (glibtop_backend *backend);
+
 glibtop_call_vector *
 glibtop_backend_get_call_vector (glibtop_backend *backend);
 
diff --git a/lib/glibtop-backend.c b/lib/glibtop-backend.c
index 6627783f..6cacfd27 100644
--- a/lib/glibtop-backend.c
+++ b/lib/glibtop-backend.c
@@ -44,6 +44,8 @@ struct _glibtop_backend_private
 {
     const glibtop_backend_info *info;
 
+    void *closure_data;
+
     glibtop_server *server;
     glibtop_backend_module *module;
 };
@@ -260,3 +262,19 @@ glibtop_backend_get_server (glibtop_backend *backend)
     return backend->_priv->server;
 }
 
+void *
+glibtop_backend_get_closure_data (glibtop_backend *backend)
+{
+    g_return_val_if_fail (GLIBTOP_IS_BACKEND (backend), NULL);
+
+    return backend->_priv->closure_data;
+}
+
+void
+glibtop_backend_set_closure_data (glibtop_backend *backend, void *closure)
+{
+    g_return_if_fail (GLIBTOP_IS_BACKEND (backend));
+    g_return_if_fail (backend->_priv->closure_data == NULL);
+
+    backend->_priv->closure_data = closure;
+}
diff --git a/lib/lib.pl b/lib/lib.pl
index 1e725fa7..a59092f3 100755
--- a/lib/lib.pl
+++ b/lib/lib.pl
@@ -179,23 +179,23 @@ sub output {
       ("\t}\n\n");
 
     $sysdeps_code .= sprintf
-      ("\tfor (list = client->_priv->backend_list; list; list = list->next) {\n\t\tglibtop_backend *backend = list->data;\n\t\tglibtop_call_vector *call_vector;\n\n\t\tcall_vector = glibtop_backend_get_call_vector (backend);\n\n\t\tif (call_vector && call_vector->%s) {\n\t\t\tglibtop_server *server = glibtop_backend_get_server (backend);\n\n", $feature);
+      ("\tfor (list = client->_priv->backend_list; list; list = list->next) {\n\t\tglibtop_backend *backend = list->data;\n\t\tglibtop_call_vector *call_vector;\n\n\t\tcall_vector = glibtop_backend_get_call_vector (backend);\n\n\t\tif (call_vector && call_vector->%s) {\n\t\t\tglibtop_server *server = glibtop_backend_get_server (backend);\n\t\t\tvoid *closure = glibtop_backend_get_closure_data (backend);\n\n", $feature);
 
     if ($line_fields[3] eq '') {
       $sysdeps_code .= sprintf
-	("\t\t\tretval = call_vector->%s (server, backend%s);\n",
+	("\t\t\tretval = call_vector->%s (server, closure%s);\n",
 	 $feature, $call_param);
     } elsif ($line_fields[3] eq 'array') {
       $sysdeps_code .= sprintf
-	("\t\t\tretval = call_vector->%s (server, backend, array%s);\n",
+	("\t\t\tretval = call_vector->%s (server, closure, array%s);\n",
 	 $feature, $call_param);
     } elsif ($line_fields[3] =~ /^array/) {
       $sysdeps_code .= sprintf
-	("\t\t\tretval = call_vector->%s (server, backend, array, buf%s);\n",
+	("\t\t\tretval = call_vector->%s (server, closure, array, buf%s);\n",
 	 $feature, $call_param);
     } else {
       $sysdeps_code .= sprintf
-	("\t\t\tretval = call_vector->%s (server, backend, buf%s);\n",
+	("\t\t\tretval = call_vector->%s (server, closure, buf%s);\n",
 	 $feature, $call_param);
     }