No exit_handler to check the error code of a program that closes about launch

[dirk-thomas]

I am not sure I understand your exact use case and how it diverges from what is possible with the existing exit handlers but the design aims to enable implementing any logic using custom handlers.

[geoffviola]

Here's the scenario. I have a launch file that starts a node and a custom parameter client. The parameter client will set the parameters and return with a zero exit code, if it ran properly. I do want the launch file to tear down if the error code is non-zero, because I don't want to run the node without the correct parameters. Currently, no exit_handler supports this scenario.

[dirk-thomas]

Likely we haven't had this use case in any of the exiting demos and examples yet. A custom written exit handler should be able to fulfill this use case. You can either keep it in your package or create a pull request to contribute it to the launch package.

[clalancette]

I'm going to close this out since I closed out the PR that implemented this. Feel free to re-open if we want to keep this feature request.