Race condition between trap_exit EXIT msg and common msg

Question

Hi the question is as following: Assume we have processes A and B which are linked. Process's A flag trap_exit is set to true. Let B process send a msg to A and then exit:

PidA ! 'msg',
exit(reason).

What I wanna know if we can be shure that the process A will receive 'msg' and only after It {'EXIT', Pid, reason} will come ? Can we predict the ordering of msgs? I can't found any proofs in documentation, but I guess that it will work that way, but I need some proofs. Don't want to have race condition here..

Answer 1

As to not leave this question hanging. This is the discussion in erlang-questions mailing list:

http://thread.gmane.org/gmane.comp.lang.erlang.general/66788

Long story short: all messages are signals (or all signals are messages), exits are seen as messages from the process, guaranteed to arrive in the same order they were sent.

Answer 2

Sounds like a code smell to me. Why do you need to rely on trap_exit? Have you thought of alternatives, e.g. proper monitoring?