diff --git a/Doc/library/multiprocessing.shared_memory.rst b/Doc/library/multiprocessing.shared_memory.rst
index 76046b34610abe..f453e6403d932d 100644
--- a/Doc/library/multiprocessing.shared_memory.rst
+++ b/Doc/library/multiprocessing.shared_memory.rst
@@ -255,16 +255,17 @@ shared memory blocks created using that manager are all released when the
:keyword:`with` statement's code block finishes execution.
-.. class:: ShareableList(sequence=None, *, name=None)
+.. class:: ShareableList(sequence=None, \*, name=None)
Provides a mutable list-like object where all values stored within are
stored in a shared memory block. This constrains storable values to
- only the ``int``, ``float``, ``bool``, ``str`` (less than 10M bytes each),
- ``bytes`` (less than 10M bytes each), and ``None`` built-in data types.
- It also notably differs from the built-in ``list`` type in that these
- lists can not change their overall length (i.e. no append, insert, etc.)
- and do not support the dynamic creation of new :class:`ShareableList`
- instances via slicing.
+ only the ``int`` (signed 64-bit), ``float``, ``bool``, ``str`` (less
+ than 10M bytes each when encoded as utf-8), ``bytes`` (less than 10M
+ bytes each), and ``None`` built-in data types. It also notably
+ differs from the built-in ``list`` type in that these lists can not
+ change their overall length (i.e. no append, insert, etc.) and do not
+ support the dynamic creation of new :class:`ShareableList` instances
+ via slicing.
*sequence* is used in populating a new ``ShareableList`` full of values.
Set to ``None`` to instead attach to an already existing
@@ -275,6 +276,35 @@ shared memory blocks created using that manager are all released when the
existing ``ShareableList``, specify its shared memory block's unique
name while leaving ``sequence`` set to ``None``.
+ .. note::
+
+ A known issue exists for :class:`bytes` and :class:`str` values.
+ If they end with ``\x00`` nul bytes or characters, those may be
+ *silently stripped* when fetching them by index from the
+ :class:`ShareableList`. This ``.rstrip(b'\x00')`` behavior is
+ considered a bug and may go away in the future. See :gh:`106939`.
+
+ For applications where rstripping of trailing nulls is a problem,
+ work around it by always unconditionally appending an extra non-0
+ byte to the end of such values when storing and unconditionally
+ removing it when fetching:
+
+ .. doctest::
+
+ >>> from multiprocessing import shared_memory
+ >>> nul_bug_demo = shared_memory.ShareableList(['?\x00', b'\x03\x02\x01\x00\x00\x00'])
+ >>> nul_bug_demo[0]
+ '?'
+ >>> nul_bug_demo[1]
+ b'\x03\x02\x01'
+ >>> nul_bug_demo.shm.unlink()
+ >>> padded = shared_memory.ShareableList(['?\x00\x07', b'\x03\x02\x01\x00\x00\x00\x07'])
+ >>> padded[0][:-1]
+ '?\x00'
+ >>> padded[1][:-1]
+ b'\x03\x02\x01\x00\x00\x00'
+ >>> padded.shm.unlink()
+
.. method:: count(value)
Returns the number of occurrences of ``value``.
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