Re: g_thread_init() and gtk_init() segmentation faults

[Olexiy Avramchenko <olexiy irtech cn ua>]

Richard Baverstock wrote:

> I'm trying to write a (GTK+2) program with multiple threads using g_thread_init(), but I have yet to figure 
> out how without receiving segmentation faults. The following is the snippet of code that invokes 
> g_thread_init() and calls gtk_init().
>
> int
> main (int argc, char *argv[])
> {
>  GtkWidget *menu_bar;
>  GtkWidget *toolbar;
>  GtkWidget *hbox1;
>  
>   g_thread_init(NULL);
>   
>   gtk_init(&argc, &argv);
>
>  bb_read_options_file ();
>  if (options.start_project)
>    options.project = options.start_project;
>
> ...
>
>
> and it goes on.
>
> Yes, it's compiled with -lgthread-2.0 and not -lgthread. Well, I actually use pkg-config --libs gthread-2.0, 
> which has that.
> Using gcc 3.2.2 with posix thread support compiled in.
>
>
> Currently, with this, I get a segmentation fault at gtk_init(&argc, &argv);. This is the output from gdb:
>
> Starting program: /home/baver/Programming/baverburner/src/baverburner 
> [New Thread 1024 (LWP 29722)]
>
> Program received signal SIGSEGV, Segmentation fault.
> [Switching to Thread 1024 (LWP 29722)]
> 0x08056bc0 in ?? ()
> (gdb) bt
> #0  0x08056bc0 in ?? ()
> #1  0x4004832a in g_main_context_new () at gmain.c:679
> #2  0x400483b9 in g_main_context_default () at gmain.c:705
> #3  0x400485c9 in g_source_attach (source=0x8068240, context=0x0) at gmain.c:820
> #4  0x402e51af in _gdk_events_init (display=0x80657e0) at gdkevents-x11.c:190
> #5  0x402dd1dd in gdk_display_open (display_name=0x0) at gdkdisplay-x11.c:217
> #6  0x402c1a0d in gdk_display_open_default_libgtk_only () at gdk.c:402
> #7  0x4014b16e in gtk_init_check (argc=0xbffff934, argv=0xbffff938) at gtkmain.c:872
> #8  0x4014b1aa in gtk_init (argc=0xbffff934, argv=0xbffff938) at gtkmain.c:901
> #9  0x0804c48d in main (argc=1, argv=0xbffff994) at main.c:55
> #10 0x40444571 in __libc_start_main () from /lib/libc.so.6
>
>
>
> I am at a total loss as to what I am doing wrong. I've tried IRC channels, forums, mailing lists archives 
> etc. It's bound to be something ironic. Anyways, if anyone can help me figure this out, it will be much 
> appreciated.
>
>
> Rich
> aka Baver
You have to use gdk_threads_init() call before gtk_init, but I can't 
imagine how this can segfault your app in single thread inside gtk_init...
If you post me the code example I'll try to check this...

Olexiy