diff --git a/hw/source/master.c b/hw/source/master.c
index 6e744c4ac..afa01cc2b 100644
--- a/hw/source/master.c
+++ b/hw/source/master.c
@@ -469,7 +469,7 @@ SV_WriteFilterList (void)
 }
 
 static void
-SV_Shutdown (void)
+SV_Shutdown (void *data)
 {
 	NET_Shutdown ();
 
@@ -525,7 +525,7 @@ main (int argc, const char **argv)
 
 	mst_cbuf = Cbuf_New (&id_interp);
 
-	Sys_RegisterShutdown (SV_Shutdown);
+	Sys_RegisterShutdown (SV_Shutdown, 0);
 
 	Sys_Init ();
 
diff --git a/include/QF/sys.h b/include/QF/sys.h
index 06e2590fa..a1a5402c7 100644
--- a/include/QF/sys.h
+++ b/include/QF/sys.h
@@ -77,7 +77,7 @@ void Sys_Error (const char *error, ...) __attribute__((format(printf,1,2), noret
 void Sys_FatalError (const char *error, ...) __attribute__((format(printf,1,2), noreturn));
 void Sys_Quit (void) __attribute__((noreturn));
 void Sys_Shutdown (void);
-void Sys_RegisterShutdown (void (*func) (void));
+void Sys_RegisterShutdown (void (*func) (void *), void *data);
 int64_t Sys_LongTime (void);
 double Sys_DoubleTime (void);
 void Sys_TimeOfDay(date_t *date);
diff --git a/include/netchan.h b/include/netchan.h
index d811ba913..cfdcf1066 100644
--- a/include/netchan.h
+++ b/include/netchan.h
@@ -70,7 +70,7 @@ void Log_Incoming_Packet (const byte *p, int len, int has_sequence,
 						  int is_server);
 void Log_Outgoing_Packet (const byte *p, int len, int has_sequence,
 						  int is_server);
-void Net_LogStop (void);
+void Net_LogStop (void *data);
 void Analyze_Client_Packet (const byte * data, int len, int has_sequence);
 void Analyze_Server_Packet (const byte * data, int len, int has_sequence);
 
diff --git a/libs/util/sys.c b/libs/util/sys.c
index 811cac886..de1cb35d8 100644
--- a/libs/util/sys.c
+++ b/libs/util/sys.c
@@ -105,7 +105,8 @@ static sys_printf_t sys_err_printf_function = Sys_ErrPrintf;
 
 typedef struct shutdown_list_s {
 	struct shutdown_list_s *next;
-	void (*func)(void);
+	void      (*func) (void *);
+	void       *data;
 } shutdown_list_t;
 
 typedef struct error_handler_s {
@@ -492,7 +493,7 @@ Sys_Shutdown (void)
 	shutdown_list_t *t;
 
 	while (shutdown_list) {
-		shutdown_list->func ();
+		shutdown_list->func (shutdown_list->data);
 		t = shutdown_list;
 		shutdown_list = shutdown_list->next;
 		free (t);
@@ -571,7 +572,7 @@ Sys_Error (const char *error, ...)
 }
 
 VISIBLE void
-Sys_RegisterShutdown (void (*func) (void))
+Sys_RegisterShutdown (void (*func) (void *), void *data)
 {
 	shutdown_list_t *p;
 	if (!func)
@@ -580,6 +581,7 @@ Sys_RegisterShutdown (void (*func) (void))
 	if (!p)
 		Sys_Error ("Sys_RegisterShutdown: insufficient memory");
 	p->func = func;
+	p->data = data;
 	p->next = shutdown_list;
 	shutdown_list = p;
 }
diff --git a/nq/include/host.h b/nq/include/host.h
index 8601ea4c2..9300abbfe 100644
--- a/nq/include/host.h
+++ b/nq/include/host.h
@@ -61,7 +61,7 @@ void Host_ClearMemory (void);
 void Host_ServerFrame (void);
 void Host_InitCommands (void);
 void Host_Init (void);
-void Host_Shutdown(void);
+void Host_Shutdown(void *data);
 void Host_Error (const char *error, ...) __attribute__((format(printf,1,2), noreturn));
 void Host_EndGame (const char *message, ...) __attribute__((format(printf,1,2), noreturn));
 void Host_Frame (float time);
diff --git a/nq/source/host.c b/nq/source/host.c
index 67b55507b..c08a4c093 100644
--- a/nq/source/host.c
+++ b/nq/source/host.c
@@ -957,7 +957,7 @@ Host_Init (void)
 	better to run quit through here before final handoff to the sys code.
 */
 void
-Host_Shutdown (void)
+Host_Shutdown (void *data)
 {
 	static qboolean isdown = false;
 
diff --git a/nq/source/sys_sdl.c b/nq/source/sys_sdl.c
index 3f4fa726e..37ff959aa 100644
--- a/nq/source/sys_sdl.c
+++ b/nq/source/sys_sdl.c
@@ -85,7 +85,7 @@ startup (void)
 }
 
 static void
-shutdown_f (void)
+shutdown_f (void *data)
 {
 #ifndef _WIN32
 	// change stdin to blocking
@@ -113,8 +113,8 @@ SDL_main (int argc, char *argv[])
 
 	isDedicated = (COM_CheckParm ("-dedicated") != 0);
 
-	Sys_RegisterShutdown (Host_Shutdown);
-	Sys_RegisterShutdown (shutdown_f);
+	Sys_RegisterShutdown (Host_Shutdown, 0);
+	Sys_RegisterShutdown (shutdown_f, 0);
 
 	Host_Init ();
 
diff --git a/nq/source/sys_unix.c b/nq/source/sys_unix.c
index ec21a1d7b..2803d31f6 100644
--- a/nq/source/sys_unix.c
+++ b/nq/source/sys_unix.c
@@ -55,7 +55,7 @@
 qboolean    isDedicated = false;
 
 static void
-shutdown_f (void)
+shutdown_f (void *data)
 {
 	// change stdin to blocking
 	fcntl (0, F_SETFL, fcntl (0, F_GETFL, 0) & ~O_NONBLOCK);
@@ -75,8 +75,8 @@ main (int argc, const char **argv)
 
 	isDedicated = (COM_CheckParm ("-dedicated") != 0);
 
-	Sys_RegisterShutdown (Host_Shutdown);
-	Sys_RegisterShutdown (shutdown_f);
+	Sys_RegisterShutdown (Host_Shutdown, 0);
+	Sys_RegisterShutdown (shutdown_f, 0);
 
 	Host_Init ();
 
diff --git a/nq/source/sys_unixd.c b/nq/source/sys_unixd.c
index 55d956268..f9ff4ca74 100644
--- a/nq/source/sys_unixd.c
+++ b/nq/source/sys_unixd.c
@@ -53,7 +53,7 @@
 qboolean    isDedicated = true;
 
 static void
-shutdown_f (void)
+shutdown_f (void *data)
 {
 	// change stdin to blocking
 	fcntl (0, F_SETFL, fcntl (0, F_GETFL, 0) & ~O_NONBLOCK);
@@ -86,8 +86,8 @@ main (int argc, const char **argv)
 	host_parms.argc = com_argc;
 	host_parms.argv = com_argv;
 
-	Sys_RegisterShutdown (Host_Shutdown);
-	Sys_RegisterShutdown (shutdown_f);
+	Sys_RegisterShutdown (Host_Shutdown, 0);
+	Sys_RegisterShutdown (shutdown_f, 0);
 
 	Host_Init ();
 
diff --git a/nq/source/sys_win.c b/nq/source/sys_win.c
index 421690748..e4593ffd0 100644
--- a/nq/source/sys_win.c
+++ b/nq/source/sys_win.c
@@ -104,7 +104,7 @@ startup (void)
 }
 
 static void
-shutdown_f (void)
+shutdown_f (void *data)
 {
 	if (tevent)
 		CloseHandle (tevent);
@@ -207,8 +207,8 @@ WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine,
 	if (!isDedicated)
 		init_handles (hInstance);
 
-	Sys_RegisterShutdown (Host_Shutdown);
-	Sys_RegisterShutdown (shutdown_f);
+	Sys_RegisterShutdown (Host_Shutdown, 0);
+	Sys_RegisterShutdown (shutdown_f, 0);
 
 	Host_Init ();
 
diff --git a/nq/source/sys_wind.c b/nq/source/sys_wind.c
index b38461448..b0555ec43 100644
--- a/nq/source/sys_wind.c
+++ b/nq/source/sys_wind.c
@@ -39,7 +39,7 @@
 qboolean    isDedicated = true;
 
 static void
-shutdown_f (void)
+shutdown_f (void *data)
 {
 }
 
@@ -69,8 +69,8 @@ main (int argc, const char **argv)
 	host_parms.argc = com_argc;
 	host_parms.argv = com_argv;
 
-	Sys_RegisterShutdown (Host_Shutdown);
-	Sys_RegisterShutdown (shutdown_f);
+	Sys_RegisterShutdown (Host_Shutdown, 0);
+	Sys_RegisterShutdown (shutdown_f, 0);
 
 	Host_Init ();
 
diff --git a/qtv/source/qtv.c b/qtv/source/qtv.c
index 4980dea9b..1274254d5 100644
--- a/qtv/source/qtv.c
+++ b/qtv/source/qtv.c
@@ -220,7 +220,7 @@ qtv_memory_init (void)
 }
 
 static void
-qtv_shutdown (void)
+qtv_shutdown (void *data)
 {
 	NET_Shutdown ();
 	Con_Shutdown ();
@@ -253,7 +253,7 @@ qtv_init (void)
 	qtv_cbuf = Cbuf_New (&id_interp);
 	qtv_args = Cbuf_ArgsNew ();
 
-	Sys_RegisterShutdown (qtv_shutdown);
+	Sys_RegisterShutdown (qtv_shutdown, 0);
 
 	Sys_Init ();
 	COM_ParseConfig ();
diff --git a/qtv/source/server.c b/qtv/source/server.c
index c664f36e4..c36465d31 100644
--- a/qtv/source/server.c
+++ b/qtv/source/server.c
@@ -508,7 +508,7 @@ sv_list_f (void)
 }
 
 static void
-server_shutdown (void)
+server_shutdown (void *data)
 {
 	Hash_FlushTable (server_hash);
 	Hash_DelTable (server_hash);
@@ -540,7 +540,7 @@ server_run (server_t *sv)
 void
 Server_Init (void)
 {
-	Sys_RegisterShutdown (server_shutdown);
+	Sys_RegisterShutdown (server_shutdown, 0);
 	server_hash = Hash_NewTable (61, server_get_key, server_free, 0);
 	Cmd_AddCommand ("sv_new", sv_new_f, "Add a new server");
 	Cmd_AddCommand ("sv_del", sv_del_f, "Remove an existing server");
diff --git a/qw/include/host.h b/qw/include/host.h
index 0c1492f47..27ad77325 100644
--- a/qw/include/host.h
+++ b/qw/include/host.h
@@ -50,7 +50,7 @@ extern int		host_framecount;	// incremented every frame, never reset
 void Host_ServerFrame (void);
 void Host_InitCommands (void);
 void Host_Init (void);
-void Host_Shutdown(void);
+void Host_Shutdown(void *data);
 void Host_Error (const char *error, ...) __attribute__((format(printf,1,2), noreturn));
 void Host_EndGame (const char *message, ...) __attribute__((format(printf,1,2), noreturn));
 void Host_Frame (float time);
diff --git a/qw/include/server.h b/qw/include/server.h
index abc5fdd9d..b32a46c63 100644
--- a/qw/include/server.h
+++ b/qw/include/server.h
@@ -488,7 +488,7 @@ client_t *SV_AllocClient (int spectator, int server);
 void SV_SavePenaltyFilter (client_t *cl, filtertype_t type, double pentime);
 double SV_RestorePenaltyFilter (client_t *cl, filtertype_t type);
 
-void SV_Shutdown (void);
+void SV_Shutdown (void *data);
 void SV_Frame (float time);
 void SV_FinalMessage (const char *message);
 void SV_DropClient (client_t *drop);
diff --git a/qw/source/cl_main.c b/qw/source/cl_main.c
index aa223736f..b78038ca9 100644
--- a/qw/source/cl_main.c
+++ b/qw/source/cl_main.c
@@ -1867,7 +1867,7 @@ Host_Init (void)
 }
 
 void
-Host_Shutdown (void)
+Host_Shutdown (void *data)
 {
 	static qboolean isdown = false;
 
diff --git a/qw/source/cl_sys_sdl.c b/qw/source/cl_sys_sdl.c
index 75f7c0024..79357134a 100644
--- a/qw/source/cl_sys_sdl.c
+++ b/qw/source/cl_sys_sdl.c
@@ -93,7 +93,7 @@ startup (void)
 }
 
 static void
-shutdown_f (void)
+shutdown_f (void *data)
 {
 #ifndef _WIN32
 	// change stdin to blocking
@@ -122,9 +122,9 @@ SDL_main (int argc, char *argv[])
 	if (!COM_CheckParm ("-noconinput"))
 		fcntl (0, F_SETFL, fcntl (0, F_GETFL, 0) | O_NONBLOCK);
 #endif
-	Sys_RegisterShutdown (Host_Shutdown);
-	Sys_RegisterShutdown (Net_LogStop);
-	Sys_RegisterShutdown (shutdown_f);
+	Sys_RegisterShutdown (Host_Shutdown, 0);
+	Sys_RegisterShutdown (Net_LogStop, 0);
+	Sys_RegisterShutdown (shutdown_f, 0);
 
 	Host_Init ();
 
diff --git a/qw/source/cl_sys_unix.c b/qw/source/cl_sys_unix.c
index 05aedf9ff..4c7071ba2 100644
--- a/qw/source/cl_sys_unix.c
+++ b/qw/source/cl_sys_unix.c
@@ -52,7 +52,7 @@
 #include "netchan.h"
 
 static void
-shutdown_f (void)
+shutdown_f (void *data)
 {
 	// change stdin to blocking
 	fcntl (0, F_SETFL, fcntl (0, F_GETFL, 0) & ~O_NONBLOCK);
@@ -73,9 +73,9 @@ main (int argc, const char **argv)
 	if (!COM_CheckParm ("-noconinput"))
 		fcntl (0, F_SETFL, fcntl (0, F_GETFL, 0) | O_NONBLOCK);
 
-	Sys_RegisterShutdown (Host_Shutdown);
-	Sys_RegisterShutdown (Net_LogStop);
-	Sys_RegisterShutdown (shutdown_f);
+	Sys_RegisterShutdown (Host_Shutdown, 0);
+	Sys_RegisterShutdown (Net_LogStop, 0);
+	Sys_RegisterShutdown (shutdown_f, 0);
 
 	Host_Init ();
 
diff --git a/qw/source/cl_sys_win.c b/qw/source/cl_sys_win.c
index 44d7c8afb..388166e7a 100644
--- a/qw/source/cl_sys_win.c
+++ b/qw/source/cl_sys_win.c
@@ -93,7 +93,7 @@ startup (void)
 }
 
 static void
-shutdown_f (void)
+shutdown_f (void *data)
 {
 	if (tevent)
 		CloseHandle (tevent);
@@ -181,9 +181,9 @@ WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine,
 	if (!tevent)
 		Sys_Error ("Couldn't create event");
 
-	Sys_RegisterShutdown (Host_Shutdown);
-	Sys_RegisterShutdown (Net_LogStop);
-	Sys_RegisterShutdown (shutdown_f);
+	Sys_RegisterShutdown (Host_Shutdown, 0);
+	Sys_RegisterShutdown (Net_LogStop, 0);
+	Sys_RegisterShutdown (shutdown_f, 0);
 
 	Host_Init ();
 
diff --git a/qw/source/net_packetlog.c b/qw/source/net_packetlog.c
index 3ec8078e5..189c6fefe 100644
--- a/qw/source/net_packetlog.c
+++ b/qw/source/net_packetlog.c
@@ -177,7 +177,7 @@ Net_LogStart (const char *fname)
 }
 
 void
-Net_LogStop (void)
+Net_LogStop (void *data)
 {
 	if (Net_PacketLog)
 		Qclose (Net_PacketLog);
@@ -954,7 +954,7 @@ Net_PacketLog_f (cvar_t *var)
 	if (var->int_val) {
 		Net_LogStart ("qfpacket.log");
 	} else {
-		Net_LogStop ();
+		Net_LogStop (0);
 	}
 }
 
diff --git a/qw/source/sv_ccmds.c b/qw/source/sv_ccmds.c
index 318a2edaf..93c5247f6 100644
--- a/qw/source/sv_ccmds.c
+++ b/qw/source/sv_ccmds.c
@@ -223,7 +223,7 @@ SV_Restart_f (void)
 							  net_message->message->data);
 	}
 	Sys_Printf ("Shutting down: server restart, shell must relaunch server\n");
-	SV_Shutdown ();
+	SV_Shutdown (0);
 	// Error code 2 on exit, indication shell must restart the server
 	exit (2);
 }
diff --git a/qw/source/sv_main.c b/qw/source/sv_main.c
index d764c012f..56d135e16 100644
--- a/qw/source/sv_main.c
+++ b/qw/source/sv_main.c
@@ -237,7 +237,7 @@ Master_Shutdown (void)
 	Quake calls this before calling Sys_Quit or Sys_Error
 */
 void
-SV_Shutdown (void)
+SV_Shutdown (void *data)
 {
 	Master_Shutdown ();
 	if (sv_fraglogfile) {
@@ -2486,7 +2486,7 @@ SV_Init (void)
 	sv_cbuf = Cbuf_New (&id_interp);
 	sv_args = Cbuf_ArgsNew ();
 
-	Sys_RegisterShutdown (SV_Shutdown);
+	Sys_RegisterShutdown (SV_Shutdown, 0);
 
 	Sys_Init ();
 	GIB_Init (true);
diff --git a/qw/source/sv_sys_unix.c b/qw/source/sv_sys_unix.c
index b3781bf5b..24b3adb4b 100644
--- a/qw/source/sv_sys_unix.c
+++ b/qw/source/sv_sys_unix.c
@@ -122,7 +122,7 @@ main (int argc, const char **argv)
 
 	SV_Init ();
 
-	Sys_RegisterShutdown (Net_LogStop);
+	Sys_RegisterShutdown (Net_LogStop, 0);
 
 	// run one frame immediately for first heartbeat
 	SV_Frame (0.1);
diff --git a/qw/source/sv_sys_win.c b/qw/source/sv_sys_win.c
index 4397f5d92..52f3b230a 100644
--- a/qw/source/sv_sys_win.c
+++ b/qw/source/sv_sys_win.c
@@ -93,7 +93,7 @@ main (int argc, const char **argv)
 	if (WinNT)
 		Cvar_Set (sys_sleep, "0");
 
-	Sys_RegisterShutdown (Net_LogStop);
+	Sys_RegisterShutdown (Net_LogStop, 0);
 
 	// run one frame immediately for first heartbeat
 	SV_Frame (0.1);
diff --git a/ruamoko/qwaq/qwaq-bi.c b/ruamoko/qwaq/qwaq-bi.c
index 7e21a9259..82bce4996 100644
--- a/ruamoko/qwaq/qwaq-bi.c
+++ b/ruamoko/qwaq/qwaq-bi.c
@@ -159,7 +159,7 @@ static builtin_t builtins[] = {
 };
 
 static void
-bi_shutdown (void)
+bi_shutdown (void *data)
 {
 	S_Shutdown ();
 	IN_Shutdown ();
@@ -177,7 +177,7 @@ BI_Init (progs_t *pr)
 	PI_Init ();
 	PI_RegisterPlugins (client_plugin_list);
 
-	Sys_RegisterShutdown (bi_shutdown);
+	Sys_RegisterShutdown (bi_shutdown, 0);
 
 	VID_Init_Cvars ();
 	IN_Init_Cvars ();
diff --git a/ruamoko/qwaq/qwaq-curses.c b/ruamoko/qwaq/qwaq-curses.c
index 6ab3f6154..27306fc28 100644
--- a/ruamoko/qwaq/qwaq-curses.c
+++ b/ruamoko/qwaq/qwaq-curses.c
@@ -921,7 +921,7 @@ process_input (qwaq_resources_t *res)
 
 static int need_endwin;
 static void
-bi_shutdown (void)
+bi_shutdown (void *_pr)
 {
 	if (need_endwin) {
 		write(1, MOUSE_MOVES_OFF, sizeof (MOUSE_MOVES_OFF) - 1);
@@ -1950,7 +1950,7 @@ BI_Init (progs_t *pr)
 
 	PR_Resources_Register (pr, "qwaq", res, bi_qwaq_clear);
 	PR_RegisterBuiltins (pr, builtins);
-	Sys_RegisterShutdown (bi_shutdown);
+	Sys_RegisterShutdown (bi_shutdown, pr);
 	logfile = fopen ("qwaq-curses.log", "wt");
 	Sys_SetStdPrintf (qwaq_print);
 }