On Tue, 5 Jul 2022 04:06:03 GMT, David Holmes <dhol...@openjdk.org> wrote:
>> Signal handlers for eg SIGTERM invoke Shutdown.shutdown. That method holds >> the same lock as Shutdown.exit and runs shutdown hooks. So if a signal >> handler triggers shutdown, and before the system halts Runtime.exit is >> invoked, the status passed to Runtime.exit will be ignored. > > First, the signal handlers actually invoke Shutdown.exit, not > Shutdown.shutdown - see Terminator.setup(). (If they did the latter, like > DestroyJavaVM, then an exit(status) call from another thread could still do > the final VM halt(status) > > But now you are opening a can of worms. There are multiple ways for the VM to > initiate termination - are you going to try and describe here how all of them > potentially interact? > > What you are really stating here is that other parts of the JDK can invoke > System.exit, but that is for them to specify where such things are specified, > it isn't for exit() to try and list them all. All we have to do here is > describe how multiple calls to exit() behave. Aha! I think I misread the comment on Shutdown.shutdown and had it stuck in my head that signals would exit through that method. Thanks for the explanation, it makes a lot more sense now. > All we have to do here is describe how multiple calls to exit() behave. The thing that is still missing to me is that an application developer may have a single call to System.exit, yet the status code they pass to it may not be the one the jvm exits with. ------------- PR: https://git.openjdk.org/jdk/pull/9351
