[Pgui-devel] Problem with pgAppMessage's

[Christian Grigis]

Hello,

I am having a problem when using pgAppMessage() between two applications.

The two attached examples (based on msgdemo) illustrate the problem:
- run recvMsg in an xterm
- run sendMsg in another xterm

msgSend creates 10 int messages numbered 0 to 9 and quickly sends them
to msgRecv.
When the sleep() call in msgRecv is removed, it correctly displays
the sequence 0..9 .
With the sleep(1), however, msgRecv displays on my machine:

[~/Development/Tests]> ./msgRecv
Received msg: 0
Received msg: 8
Received msg: 8
Received msg: 8
Received msg: 8
Received msg: 8
Received msg: 8
Received msg: 8
Received msg: 8
Received msg: 9

Essentially, messages are lost when the receiver is slow to process them.

Are APPMSG's not queued for the receiver?

Thanks for any help!

-Christian

-- 
Christian Grigis                        |       SMARTDATA SA
Software Engineer                       |       PSE-A / EPFL
Phone: +41-(21)-693-84-98               |       CH - 1015 Lausanne
mailto:[EMAIL PROTECTED]    |       http://www.smartdata.ch



#include <picogui.h>

void sendMsg (int * msg)
{
  pghandle peer;
  int * dup;

  peer = pgFindWidget ("TestReceiver");
  if (!peer)
    {
      printf ("Can't find receiver\n");
      exit (1);
    }

  dup = (int *) malloc (sizeof (int));
  *dup = *msg;
  pgAppMessage (peer, pgFromTempMemory (dup, sizeof (int)));
}

int main (int argc, char * argv [])
{
  int msg;

  pgInit (argc, argv);
  pgRegisterApp (PG_APP_NORMAL, "Send", 0);

  for (msg = 0; msg < 10; msg++)
    {
      sendMsg (&msg);
    }

  pgFlushRequests ();

  return 0;
}

#include <picogui.h>

int evt_handler (struct pgEvent * evt)
{
  int msg;

  msg = * ((int *) evt->e.data.pointer);
  printf ("Received msg: %d\n", msg);
  sleep (1);

  return 0;
}

int main (int argc, char * argv [])
{
  pgInit (argc, argv);
  pgRegisterApp (PG_APP_NORMAL, "Recv", 0);
  pgSetWidget (PGDEFAULT,
               PG_WP_NAME, pgNewString ("TestReceiver"),
               0);

  pgBind (PGDEFAULT, PG_WE_APPMSG, &evt_handler, NULL);

  pgEventLoop ();

  return 0;
}