Issue #12011: signal.signal() and signal.siginterrupt() raise an OSError,
instead of a RuntimeError: OSError has an errno attribute.
diff --git a/Doc/whatsnew/3.3.rst b/Doc/whatsnew/3.3.rst
index e657af2..d442665 100644
--- a/Doc/whatsnew/3.3.rst
+++ b/Doc/whatsnew/3.3.rst
@@ -148,6 +148,9 @@
a nul byte into the wakeup file descriptor. So it is possible to wait more
than one signal and know which signals were raised.
+* :func:`signal.signal` and :func:`signal.siginterrupt` raise an OSError,
+ instead of a RuntimeError: OSError has an errno attribute.
+
Optimizations
=============