bpo-33332: Add signal.valid_signals() (GH-6581)
diff --git a/Doc/library/signal.rst b/Doc/library/signal.rst
index 3f17e08..67ee979 100644
--- a/Doc/library/signal.rst
+++ b/Doc/library/signal.rst
@@ -216,6 +216,15 @@
.. versionadded:: 3.8
+.. function:: valid_signals()
+
+ Return the set of valid signal numbers on this platform. This can be
+ less than ``range(1, NSIG)`` if some signals are reserved by the system
+ for internal use.
+
+ .. versionadded:: 3.8
+
+
.. function:: pause()
Cause the process to sleep until a signal is received; the appropriate handler
@@ -268,8 +277,8 @@
argument.
*mask* is a set of signal numbers (e.g. {:const:`signal.SIGINT`,
- :const:`signal.SIGTERM`}). Use ``range(1, signal.NSIG)`` for a full mask
- including all signals.
+ :const:`signal.SIGTERM`}). Use :func:`~signal.valid_signals` for a full
+ mask including all signals.
For example, ``signal.pthread_sigmask(signal.SIG_BLOCK, [])`` reads the
signal mask of the calling thread.