gtk多线程例子

gtk多线程例子，来源于gtk  demo，作者 Erik Mouw

/*-------------------------------------------------------------------------
 * Filename: gtk_thread.c
 * Version: 0.99.1
 * Copyright: Copyright (C) 1999, Erik Mouw
 * Author: Erik Mouw <[e-mail]>
 * Description: GTK threads example.
 * Created at: Sun Oct 17 21:27:09 1999
 * Modified by: Erik Mouw <[e-mail]>
 * Modified at: Sun Oct 24 17:21:41 1999
 *-----------------------------------------------------------------------*/
/*
 * Compile with:
 *
 * cc -o gtk_thread gtk_thread.c `gtk-config --cflags --libs gthread`
 *
 * Thanks to Sebastian Wilhelmi and Owen Taylor for pointing out some
 * bugs.
 *
 */
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <time.h>
#include <gtk/gtk.h>
#include <glib.h>
#include <pthread.h>
#define YES_IT_IS (1)
#define NO_IT_IS_NOT (0)
typedef struct
{
  GtkWidget *label;
  int what;
} yes_or_no_args;
G_LOCK_DEFINE_STATIC (yes_or_no);
static volatile int yes_or_no = YES_IT_IS;
void destroy (GtkWidget *widget, gpointer data)
{
  gtk_main_quit ();
}
void *argument_thread (void *args)
{
  yes_or_no_args *data = (yes_or_no_args *)args;
  gboolean say_something;
  for (;;)
    {
      /* sleep a while */
      sleep(rand() / (RAND_MAX / 3) + 1);
      /* lock the yes_or_no_variable */
      G_LOCK(yes_or_no);
      /* do we have to say something? */
      say_something = (yes_or_no != data->what);
      if(say_something)
    {
      /* set the variable */
      yes_or_no = data->what;
    }
      /* Unlock the yes_or_no variable */
      G_UNLOCK (yes_or_no);
      if (say_something)
    {
      /* get GTK thread lock */
      gdk_threads_enter ();
      /* set label text */
      if(data->what == YES_IT_IS)
        gtk_label_set_text (GTK_LABEL (data->label), "O yes, it is!");
      else
        gtk_label_set_text (GTK_LABEL (data->label), "O no, it isn't!");
      /* release GTK thread lock */
      gdk_threads_leave ();
    }
    }
  return NULL;
}
int main (int argc, char *argv[])
{
  GtkWidget *window;
  GtkWidget *label;
  yes_or_no_args yes_args, no_args;
  pthread_t no_tid, yes_tid;
  /* init threads */
  g_thread_init (NULL);
  gdk_threads_init ();
  gdk_threads_enter ();
  /* init gtk */
  gtk_init(&argc, &argv);
  /* init random number generator */
  srand ((unsigned int) time (NULL));
  /* create a window */
  window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
  g_signal_connect (window, "destroy", G_CALLBACK (destroy), NULL);
  gtk_container_set_border_width (GTK_CONTAINER (window), 10);
  /* create a label */
  label = gtk_label_new ("And now for something completely different ...");
  gtk_container_add (GTK_CONTAINER (window), label);
  /* show everything */
  gtk_widget_show (label);
  gtk_widget_show (window);
  /* create the threads */
  yes_args.label = label;
  yes_args.what = YES_IT_IS;
  pthread_create (&yes_tid, NULL, argument_thread, &yes_args);
  no_args.label = label;
  no_args.what = NO_IT_IS_NOT;
  pthread_create (&no_tid, NULL, argument_thread, &no_args);
  /* enter the GTK main loop */
  gtk_main ();
  gdk_threads_leave ();
  return 0;
}