Issue #23400: Add notes about the sem_open support of the host OS to
"Pipes and Queues" and "Synchronization between processes" subsections.
Patch by Davin Potts.
diff --git a/Doc/library/multiprocessing.rst b/Doc/library/multiprocessing.rst
index 77cb877..021e3c8 100644
--- a/Doc/library/multiprocessing.rst
+++ b/Doc/library/multiprocessing.rst
@@ -160,14 +160,6 @@
Without using the lock output from the different processes is liable to get all
mixed up.
-.. warning::
-
- Some of this package's functionality requires a functioning shared semaphore
- implementation on the host operating system. Without one, the
- :mod:`multiprocessing.synchronize` module will be disabled, and attempts to
- import it will result in an :exc:`ImportError`. See
- :issue:`3770` for additional information.
-
Sharing state between processes
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
@@ -659,6 +651,15 @@
immediately without waiting to flush enqueued data to the
underlying pipe, and you don't care about lost data.
+ .. note::
+
+ This class's functionality requires a functioning shared semaphore
+ implementation on the host operating system. Without one, the
+ functionality in this class will be disabled, and attempts to
+ instantiate a :class:`Queue` will result in an :exc:`ImportError`. See
+ :issue:`3770` for additional information. The same holds true for any
+ of the specialized queue types listed below.
+
.. class:: multiprocessing.queues.SimpleQueue()
@@ -965,6 +966,14 @@
This differs from the behaviour of :mod:`threading` where SIGINT will be
ignored while the equivalent blocking calls are in progress.
+.. note::
+
+ Some of this package's functionality requires a functioning shared semaphore
+ implementation on the host operating system. Without one, the
+ :mod:`multiprocessing.synchronize` module will be disabled, and attempts to
+ import it will result in an :exc:`ImportError`. See
+ :issue:`3770` for additional information.
+
Shared :mod:`ctypes` Objects
~~~~~~~~~~~~~~~~~~~~~~~~~~~~