Re: drawing area won't refresh on X11 unless touched, app ismultithreaded, gtk 2.0

["Jimmy Firewire" <trigonometric softhome net>]

> > I created a new thread for gtk_main using pthreads so that I could do
the
> > active drawing on the drawing area in the remainder of the normal c main
> > function. All I then do is this:
>
> I presume you read the threading FAQs and docs on using GTK (and GDK)
> with threads?

No.

> If you initialized the threading system properly and use
> the enter and leave critical sections for all GTK and GDK calls, then
> threading will work just fine and the GUI will update normally.  Sounds
> like you haven't done this.

I don't currently have any critical sections. The documentation says that
g_thread_init() makes glib thread aware, it would seem to talk about thread
safety, which I don't really care about right now since I don't think I need
mutual exclusion.

But in any case I just added g_thread_init();

but before it even gets to the threading of gtk_main it barfs on line 151 of
test.c which is just:

gtk_widget_show(window);

here is the backtrace:

#0  0x00000000 in ?? ()
#1  0x286722a0 in g_thread_self () from /usr/local/lib/libglib-2.0.so.400
#2  0x28671669 in g_static_private_set ()
   from /usr/local/lib/libglib-2.0.so.400
#3  0x2863049a in g_module_open () from /usr/local/lib/libgmodule-2.0.so.400
#4  0x285cd91c in pango_module_load () from
/usr/X11R6/lib/libpango-1.0.so.399
#5  0x2861def9 in g_type_module_use ()
   from /usr/local/lib/libgobject-2.0.so.400
#6  0x285cdbab in pango_engine_pair_get_engine ()
   from /usr/X11R6/lib/libpango-1.0.so.399
#7  0x285ce57a in append_engines () from /usr/X11R6/lib/libpango-1.0.so.399
#8  0x285ce610 in pango_map_get_engines ()
   from /usr/X11R6/lib/libpango-1.0.so.399
#9  0x285d1cad in get_engines () from /usr/X11R6/lib/libpango-1.0.so.399
#10 0x285d1e12 in get_shaper_and_font ()
   from /usr/X11R6/lib/libpango-1.0.so.399
#11 0x285d22cd in itemize_state_process_run ()
   from /usr/X11R6/lib/libpango-1.0.so.399
#12 0x285d2578 in pango_itemize_with_base_dir ()
   from /usr/X11R6/lib/libpango-1.0.so.399
#13 0x285da1ea in pango_layout_check_lines ()
   from /usr/X11R6/lib/libpango-1.0.so.399
#14 0x285d844f in pango_layout_get_extents_internal ()
#15 0x285d873f in pango_layout_get_extents ()
   from /usr/X11R6/lib/libpango-1.0.so.399
#16 0x2817c051 in gtk_label_get () from /usr/X11R6/lib/libgtk-x11-2.0.so.400
#17 0x28613723 in g_cclosure_marshal_VOID__BOXED ()
   from /usr/local/lib/libgobject-2.0.so.400
#18 0x285fe3e7 in g_type_class_meta_marshal ()
   from /usr/local/lib/libgobject-2.0.so.400
#19 0x285fe0e9 in g_closure_invoke () from
/usr/local/lib/libgobject-2.0.so.400
#20 0x28612076 in signal_emit_unlocked_R ()
   from /usr/local/lib/libgobject-2.0.so.400
#21 0x28611815 in g_signal_emit_valist ()
   from /usr/local/lib/libgobject-2.0.so.400
#22 0x28611c26 in g_signal_emit_by_name ()
   from /usr/local/lib/libgobject-2.0.so.400
#23 0x281dd991 in gtk_size_group_remove_widget ()
   from /usr/X11R6/lib/libgtk-x11-2.0.so.400
#24 0x281ddd18 in gtk_size_group_remove_widget ()
   from /usr/X11R6/lib/libgtk-x11-2.0.so.400
#25 0x28295d37 in gtk_widget_size_request ()
   from /usr/X11R6/lib/libgtk-x11-2.0.so.400
#26 0x280d1d3b in gtk_button_get_relief ()
   from /usr/X11R6/lib/libgtk-x11-2.0.so.400
#27 0x28613723 in g_cclosure_marshal_VOID__BOXED ()
   from /usr/local/lib/libgobject-2.0.so.400
#28 0x285fe3e7 in g_type_class_meta_marshal ()
   from /usr/local/lib/libgobject-2.0.so.400
#29 0x285fe0e9 in g_closure_invoke () from
/usr/local/lib/libgobject-2.0.so.400
#30 0x28612076 in signal_emit_unlocked_R ()
   from /usr/local/lib/libgobject-2.0.so.400
#31 0x28611815 in g_signal_emit_valist ()
   from /usr/local/lib/libgobject-2.0.so.400
#32 0x28611c26 in g_signal_emit_by_name ()
   from /usr/local/lib/libgobject-2.0.so.400
#33 0x281dd991 in gtk_size_group_remove_widget ()
   from /usr/X11R6/lib/libgtk-x11-2.0.so.400
#34 0x281ddd18 in gtk_size_group_remove_widget ()
   from /usr/X11R6/lib/libgtk-x11-2.0.so.400
#35 0x28295d37 in gtk_widget_size_request ()
   from /usr/X11R6/lib/libgtk-x11-2.0.so.400
#36 0x2828db3e in gtk_vbox_new () from /usr/X11R6/lib/libgtk-x11-2.0.so.400
#37 0x28613723 in g_cclosure_marshal_VOID__BOXED ()
   from /usr/local/lib/libgobject-2.0.so.400
#38 0x285fe3e7 in g_type_class_meta_marshal ()
   from /usr/local/lib/libgobject-2.0.so.400
#39 0x285fe0e9 in g_closure_invoke () from
/usr/local/lib/libgobject-2.0.so.400
#40 0x28612076 in signal_emit_unlocked_R ()
   from /usr/local/lib/libgobject-2.0.so.400
#41 0x28611815 in g_signal_emit_valist ()
   from /usr/local/lib/libgobject-2.0.so.400
#42 0x28611c26 in g_signal_emit_by_name ()
   from /usr/local/lib/libgobject-2.0.so.400
#43 0x281dd991 in gtk_size_group_remove_widget ()
   from /usr/X11R6/lib/libgtk-x11-2.0.so.400
#44 0x281ddd18 in gtk_size_group_remove_widget ()
   from /usr/X11R6/lib/libgtk-x11-2.0.so.400
#45 0x28295d37 in gtk_widget_size_request ()
   from /usr/X11R6/lib/libgtk-x11-2.0.so.400
#46 0x282a606c in gtk_window_reshow_with_initial_size ()
   from /usr/X11R6/lib/libgtk-x11-2.0.so.400
#47 0x28613723 in g_cclosure_marshal_VOID__BOXED ()
   from /usr/local/lib/libgobject-2.0.so.400
#48 0x285fe3e7 in g_type_class_meta_marshal ()
   from /usr/local/lib/libgobject-2.0.so.400
#49 0x285fe0e9 in g_closure_invoke () from
/usr/local/lib/libgobject-2.0.so.400
#50 0x28612076 in signal_emit_unlocked_R ()
   from /usr/local/lib/libgobject-2.0.so.400
#51 0x28611815 in g_signal_emit_valist ()
   from /usr/local/lib/libgobject-2.0.so.400
#52 0x28611c26 in g_signal_emit_by_name ()
   from /usr/local/lib/libgobject-2.0.so.400
#53 0x281dd991 in gtk_size_group_remove_widget ()
   from /usr/X11R6/lib/libgtk-x11-2.0.so.400
#54 0x281ddd18 in gtk_size_group_remove_widget ()
   from /usr/X11R6/lib/libgtk-x11-2.0.so.400
#55 0x28295d37 in gtk_widget_size_request ()
   from /usr/X11R6/lib/libgtk-x11-2.0.so.400
#56 0x282a7168 in gtk_window_propagate_key_event ()
   from /usr/X11R6/lib/libgtk-x11-2.0.so.400
#57 0x282a5761 in gtk_window_reshow_with_initial_size ()
   from /usr/X11R6/lib/libgtk-x11-2.0.so.400
#58 0x28612b99 in g_cclosure_marshal_VOID__VOID ()
   from /usr/local/lib/libgobject-2.0.so.400
#59 0x285fe3e7 in g_type_class_meta_marshal ()
   from /usr/local/lib/libgobject-2.0.so.400
#60 0x285fe0e9 in g_closure_invoke () from
/usr/local/lib/libgobject-2.0.so.400
#61 0x28612076 in signal_emit_unlocked_R ()
   from /usr/local/lib/libgobject-2.0.so.400
#62 0x28611815 in g_signal_emit_valist ()
   from /usr/local/lib/libgobject-2.0.so.400
#63 0x28611ab4 in g_signal_emit () from /usr/local/lib/libgobject-2.0.so.400
#64 0x28294a3a in gtk_widget_show () from
/usr/X11R6/lib/libgtk-x11-2.0.so.400
#65 0x080493ae in main (argc=1, argv=0xbfbfe988) at test.c:151
#66 0x08048dd2 in _start ()

Lovely huh? Any ideas?

I've read glib thread docs and the FAQ entry but I couldn't find anything
that said about getting windows to refresh, only stuff about thread safety,
do you know from experience that this is a thread problem that causes my
window not to refresh properly?

Does that backtrace above look familiar? Perhaps I messed up my UNIX system?

trigonometric