More thread problems

[Ola Andersson <rand ling umu se>]

Why can't I access the gtk_label from a thread
in the program below? I'm using v1.2.6 of glib
and gtk+ (with the patch to gdataset.c I got from
this list).

I linked this program with:
 -lpthread -lgthread -lgtk -lgdk -lX11 -lglib

---

#include <gtk/gtk.h>
#include <pthread.h>

GtkWidget *label;
pthread_t tid;

void *thread(void *arg)
{
  gtk_label_set_text(GTK_LABEL(label),"Hello World");
  return NULL;
}

void change_label(GtkWidget *widget,gpointer data)
{
  pthread_create(&tid,NULL,thread,NULL);
}

int main(int argc,char **argv)
{
  GtkWidget *window,*button,*box;

  g_thread_init(NULL);
  gtk_init(&argc, &argv);
  window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
  gtk_container_set_border_width(GTK_CONTAINER(window),10);
  label = gtk_label_new("label");
  box = gtk_vbox_new(FALSE, 0);
  gtk_box_pack_start(GTK_BOX(box),label,FALSE,FALSE,0);
  gtk_widget_show(label);
  button = gtk_button_new_with_label("Change label");
  gtk_box_pack_start(GTK_BOX(box),button,FALSE,FALSE,0);
  gtk_widget_show(button);
 
gtk_signal_connect(GTK_OBJECT(button),"clicked",GTK_SIGNAL_FUNC(change_label),NULL);
  gtk_container_add(GTK_CONTAINER(window),box);
  gtk_widget_show(box);
  gtk_widget_show(window);
  gdk_threads_enter();
  gtk_main();
  gdk_threads_leave();
  return 0;
}

-- 
Ola Andersson                       mailto:rand@ling.umu.se
Research Engineer                   http://www.ling.umu.se/~rand
Department of Phonetics             Phone: +46 90 786 56 81
Umea University                     Fax:   +46 90 786 63 77