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+## SIGKILL/SIGSTOP can not be trapped.
+
+### Problematic code:
+
+```sh
+trap 'echo "unkillable"' KILL
+```
+
+### Correct code:
+
+Not applicable. This is not possible.
+
+### Rationale:
+
+SIGKILL and SIGSTOP can not be caught/ignored (according to POSIX and as implemented on platforms including Linux and FreeBSD). Trying to trap this signal has undefined results.
+
+### Exceptions:
+
+None. If you come across one, please file an issue about it.
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