Обслуживание приложения Java, работающего на одном порту, через сервер nginx, работающий на другом

Когда у меня возник тот же вопрос, это помогло мне.

When you successfully use exec, the exec'd program replaces your shell. The exec'd program's exit status is sent back to the parent process that executed your shell.

The only way that exec's exit status can be interpreted by the line following exec is if the exec calls fails, normally only if the command requested does not exist or if the file is not executable. This does not include option parsing problems, since those are parsed by the exec'd program once it is started.

If you want your shell to interpret the exit code of a program, you cannot use exec to do it. Just run the program in your shell, and when it finishes you can consult the exit status.

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