This is a multi threaded application that uses a progress bar to show

status.  It uses Gtk+ to make a smooth pulse. Written by Jud Bishop

docs/examples/smooth-gtk-thread.c

@@ -0,0 +1,217 @@
+/*****************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \___|\___/|_| \_\_____|
+ *
+ * $Id$
+ *
+ * This is a multi threaded application that uses a progress bar to show
+ * status.  It uses Gtk+ to make a smooth pulse.
+ *
+ * Written by Jud Bishop after studying the other examples provided with
+ * libcurl.
+ *
+ * To compile (on a single line):
+ * gcc -ggdb `pkg-config --cflags  --libs gtk+-2.0` -lcurl -lssl -lcrypto
+ *   -lgthread-2.0 -dl  smooth-gtk-thread.c -o smooth-gtk-thread
+ */
+
+#include <stdio.h>
+#include <gtk/gtk.h>
+#include <glib.h>
+#include <unistd.h>
+#include <pthread.h>
+
+#include <curl/curl.h>
+#include <curl/types.h> /* new for v7 */
+#include <curl/easy.h> /* new for v7 */
+
+#define NUMT 4
+
+pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
+int j = 0;
+gint num_urls = 9; /* Just make sure this is less than urls[]*/
+char *urls[]= {
+  "90022",
+  "90023",
+  "90024",
+  "90025",
+  "90026",
+  "90027",
+  "90028",
+  "90029",
+  "90030"
+};
+
+size_t write_file(void *ptr, size_t size, size_t nmemb, FILE *stream)
+{
+  /* printf("write_file\n"); */
+  return fwrite(ptr, size, nmemb, stream);
+}
+
+/* http://xoap.weather.com/weather/local/46214?cc=*&dayf=5&unit=i */
+void *pull_one_url(void *NaN)
+{
+  CURL *curl;
+  CURLcode res;
+  gchar *http;
+  FILE *outfile;
+  gint i;
+
+  /* Stop threads from entering unless j is incremented */
+  pthread_mutex_lock(&lock);
+  while ( j < num_urls )
+  {
+    printf("j = %d\n", j);
+
+    http =
+      g_strdup_printf("xoap.weather.com/weather/local/%s?cc=*&dayf=5&unit=i\n",
+                      urls[j]);
+
+    printf( "http %s", http );
+
+    curl = curl_easy_init();
+    if(curl)
+    {
+
+      outfile = fopen(urls[j], "w");
+      /* printf("fopen\n"); */
+
+      /* Set the URL and transfer type */
+      curl_easy_setopt(curl, CURLOPT_URL, http);
+
+      /* Write to the file */
+      curl_easy_setopt(curl, CURLOPT_WRITEDATA, outfile);
+      curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_file);
+
+      j++;  /* critical line */
+      pthread_mutex_unlock(&lock);
+
+      res = curl_easy_perform(curl);
+
+      fclose(outfile);
+      printf("fclose\n");
+
+      curl_easy_cleanup(curl);
+    }
+    g_free (http);
+
+    /* Adds more latency, testing the mutex.*/
+    sleep(1);
+
+  } /* end while */
+  return NULL;
+}
+
+
+gboolean pulse_bar(gpointer data)
+{
+  gdk_threads_enter();
+  gtk_progress_bar_pulse (GTK_PROGRESS_BAR (data));
+  gdk_threads_leave();
+
+  /* Return true so the function will be called again;
+   * returning false removes this timeout function.
+   */
+  return TRUE;
+}
+
+void *create_thread(void *progress_bar)
+{
+  pthread_t tid[NUMT];
+  int i;
+  int error;
+
+  /* Make sure I don't create more threads than urls. */
+  for(i=0; i < NUMT && i < num_urls ; i++) {
+    error = pthread_create(&tid[i],
+                           NULL, /* default attributes please */
+                           pull_one_url,
+                           NULL);
+    if(0 != error)
+      fprintf(stderr, "Couldn't run thread number %d, errno %d\n", i, error);
+    else
+      fprintf(stderr, "Thread %d, gets %s\n", i, urls[i]);
+  }
+
+  /* Wait for all threads to terminate. */
+  for(i=0; i < NUMT && i < num_urls; i++) {
+    error = pthread_join(tid[i], NULL);
+    fprintf(stderr, "Thread %d terminated\n", i);
+  }
+
+  /* This stops the pulsing if you have it turned on in the progress bar
+     section */
+  g_source_remove(GPOINTER_TO_INT(g_object_get_data(G_OBJECT(progress_bar),
+                                                    "pulse_id")));
+
+  /* This destroys the progress bar */
+  gtk_widget_destroy(progress_bar);
+
+  /* [Un]Comment this out to kill the program rather than pushing close. */
+  /* gtk_main_quit(); */
+
+
+  return NULL;
+
+}
+
+static gboolean cb_delete(GtkWidget *window, gpointer data)
+{
+  gtk_main_quit();
+  return FALSE;
+}
+
+int main(int argc, char **argv)
+{
+  GtkWidget *top_window, *outside_frame, *inside_frame, *progress_bar;
+  GtkAdjustment *adj;
+
+  /* Init thread */
+  g_thread_init(NULL);
+  gdk_threads_init ();
+  gdk_threads_enter ();
+
+  gtk_init(&argc, &argv);
+
+  /* Base window */
+  top_window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
+
+  /* Frame */
+  outside_frame = gtk_frame_new(NULL);
+  gtk_frame_set_shadow_type(GTK_FRAME(outside_frame), GTK_SHADOW_OUT);
+  gtk_container_add(GTK_CONTAINER(top_window), outside_frame);
+
+  /* Frame */
+  inside_frame = gtk_frame_new(NULL);
+  gtk_frame_set_shadow_type(GTK_FRAME(inside_frame), GTK_SHADOW_IN);
+  gtk_container_set_border_width(GTK_CONTAINER(inside_frame), 5);
+  gtk_container_add(GTK_CONTAINER(outside_frame), inside_frame);
+
+  /* Progress bar */
+  progress_bar = gtk_progress_bar_new();
+  gtk_progress_bar_pulse (GTK_PROGRESS_BAR (progress_bar));
+  /* Make uniform pulsing */
+  gint pulse_ref = g_timeout_add (300, pulse_bar, progress_bar);
+  g_object_set_data(G_OBJECT(progress_bar), "pulse_id",
+                    GINT_TO_POINTER(pulse_ref));
+  gtk_container_add(GTK_CONTAINER(inside_frame), progress_bar);
+
+  gtk_widget_show_all(top_window);
+  printf("gtk_widget_show_all\n");
+
+  g_signal_connect(G_OBJECT (top_window), "delete-event",
+                   G_CALLBACK(cb_delete), NULL);
+
+  if (!g_thread_create(&create_thread, progress_bar, FALSE, NULL) != 0)
+    g_warning("can't create the thread");
+
+  gtk_main();
+  gdk_threads_leave();
+  printf("gdk_threads_leave\n");
+
+  return 0;
+}
+