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mazdak
bd2c228b57
## Type of Change - [x] Bug fix - [ ] New feature - [ ] Breaking change - [ ] Documentation update ## Description Correct signal semantics for plugins: Container binary currently execs into plugin binaries. If the parent CLI keeps SIGINT/SIGTERM handlers installed, it can intercept/alter signal behavior intended for the plugin (e.g., preventing graceful shutdown in foreground workflows). ## Motivation and Context During the development of a plugin (docker compose compatibility plugin), I encountered a major issues where CTRL-C (SIGTERM) was not being sent to my plugin. CLI plugins, especially those that have long running tasks need a way to handle signals from the OS. Current, we exec into plugin binaries. If the parent CLI keeps SIGINT/SIGTERM handlers installed, it can intercept/alter signal behavior intended for the plugin (e.g., preventing graceful shutdown in foreground workflows). ### What we changed: - Signals handed back to plugins: - DefaultCommand resets SIGINT/SIGTERM to defaults immediately before exec’ing the plugin. - Rationale: since exec replaces the process image, signals should be delivered to (and handled by) the plugin without parent interference. - Non‑plugin commands remain unaffected by this change. - Compatibility: No change to plugin ABI or exec flow. ### Alternatives considered: - Supervising child instead of exec: central forwarding of signals from parent to plugin. Rejected for now to avoid changing process tree/stdio semantics; resetting to defaults before exec preserves current model while fixing signal interference. ## Testing - [X] Tested locally - [ ] Added/updated tests - [ ] Added/updated docs