Race conditions with GenServer.call and exit from handle_call?

Questions / Help
1

Hi,

I am using GenServer.call to send some information to a GenServer process. Under some conditions, the GenServer will reply to the caller (GenServer.reply) and then stop normally with a {:stop, ...} return.

I can see in gen:do_call/4 that the calling process is waiting for a reply and a 'DOWN' message. Does monitors respect the rule that messages sent from a process to another are always delivered in order, or is it possible that the calling process receives the down message before the reply ?

I want to know if I can safely avoid to use a wrapping try/catch for the normal case when the server behaves as expected (i.e. send a reply then stop).

2

The message and signal ordering is guaranteed by the underlying system and BEAM. So your explicit reply message will arrive before the 'DOWN' message coming from the process terminating.

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3

Thanks @rvirding !