gstreamer C API

[R C]

Hello,


I have been playing with the "basic tutorial" C API a bit, and can 
create a stream in c code. However, when the strea is running, how can I 
quit/terminate that stream?


For example,  basic tutorial 3:


After creating a pipeline, one can start it. Then there's a loop that 
listens for msgs from the 'bus', in a loop. Whenever there is a msg, the 
loop runs through a switch, and and listens for a new msg again.

I want to create "some sort of event"  that terminates that loop (for 
example existence (or not) of a lock file.).

(or can I create a handler, set an option, that will make 
gst_element_get_bus(..)  return, even if there isn't a msg, with an 
empty msg or so?  (I am fairly sure, gst_element_get_bus, is not 
returning and only will if there is a msg waiting.)


Here's a/the code snippet from the basic tutorial 3 example:

   /* Start playing */
   ret = gst_element_set_state (data.pipeline, GST_STATE_PLAYING);
   if (ret == GST_STATE_CHANGE_FAILURE) {
     g_printerr ("Unable to set the pipeline to the playing state.\n");
     gst_object_unref (data.pipeline);
     return -1;
   }

   /* Listen to the bus */
   bus = gst_element_get_bus (data.pipeline);
   do {
     msg = gst_bus_timed_pop_filtered (bus, GST_CLOCK_TIME_NONE,
         GST_MESSAGE_STATE_CHANGED | GST_MESSAGE_ERROR | GST_MESSAGE_EOS);

     /* Parse message */
     if (msg != NULL) {
       GError *err;
       gchar *debug_info;

       switch (GST_MESSAGE_TYPE (msg)) {
         case GST_MESSAGE_ERROR:
           gst_message_parse_error (msg, &err, &debug_info);
           g_printerr ("Error received from element %s: %s\n", 
GST_OBJECT_NAME (msg->src), err->message);
           g_printerr ("Debugging information: %s\n", debug_info ? 
debug_info : "none");
           g_clear_error (&err);
           g_free (debug_info);
           terminate = TRUE;
           break;
         case GST_MESSAGE_EOS:
           g_print ("End-Of-Stream reached.\n");
           terminate = TRUE;
           break;
         case GST_MESSAGE_STATE_CHANGED:
           /* We are only interested in state-changed messages from the 
pipeline */
           if (GST_MESSAGE_SRC (msg) == GST_OBJECT (data.pipeline)) {
             GstState old_state, new_state, pending_state;
             gst_message_parse_state_changed (msg, &old_state, 
&new_state, &pending_state);
             g_print ("Pipeline state changed from %s to %s:\n",
                 gst_element_state_get_name (old_state), 
gst_element_state_get_name (new_state));
           }
           break;
         default:
           /* We should not reach here */
           g_printerr ("Unexpected message received.\n");
           break;
       }
       gst_message_unref (msg);
     }
   } while (!terminate);
















-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.freedesktop.org/archives/gstreamer-devel/attachments/20190531/a236940c/attachment.html>