Note that the question of "what layout does `siginfo_t` have here? (in particular, when to check the signal number vs the signal code)" is quite nontrivial. For

Note that the question of "what layout does `siginfo_t` have here? (in particular, when to check the signal number vs the signal code)" is quite nontrivial. For the full answer, see the kernel's `siginfo_layout`. Note that there's an abominable case of the USB asyncio accessing the wrong member. [1]: https://elixir.bootlin.com/linux/v6.9.7/source/kernel/signal.c#L3332 https://elixir.bootlin.com/linux/v6.9.7/source/kernel/signal...