Hello,

under certain circumstances, my system runs into a never ending message ping-pong between mqueue and another process. I 
was able to break this ping-pong and got a kernel event log.

It shows, that a Send Message from my process is answered with Error from mqueue (orange IPC arrow in timeline view).
The code of my process would handle a return value of -1 of mq_send(), but it seems to return 0.
I read the description of Communication event Error. It says, that the client (mqueue) calls MsgError() in that case. 
The description of MsgError() says, that it sets errno according to the given error parameter and returns MsgSend() with
 return value -1. Only if the given error parameter is 0, MsgSend() will return 0 (EOK).

So I assume, that MsgError() was called with error = 0 within mqueue. How can I now catch that error in my process?