gh-108014: Add Py_IsFinalizing() function (#108032)

Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>

3 files changed, 17 insertions, 5 deletions

diff --git a/Doc/c-api/init.rst b/Doc/c-api/init.rst
index dd53fe2..60f5c81 100644
--- a/Doc/c-api/init.rst
+++ b/Doc/c-api/init.rst
@@ -373,6 +373,14 @@ Initializing and finalizing the interpreter
    :c:func:`Py_Initialize` is called again.
 
 
+.. c:function:: int Py_IsFinalizing()
+
+   Return true (non-zero) if the main Python interpreter is
+   :term:`shutting down <interpreter shutdown>`. Return false (zero) otherwise.
+
+   .. versionadded:: 3.13
+
+
 .. c:function:: int Py_FinalizeEx()
 
    Undo all initializations made by :c:func:`Py_Initialize` and subsequent use of
@@ -852,7 +860,7 @@ code, or when embedding the Python interpreter:
    .. note::
       Calling this function from a thread when the runtime is finalizing
       will terminate the thread, even if the thread was not created by Python.
-      You can use :c:func:`!_Py_IsFinalizing` or :func:`sys.is_finalizing` to
+      You can use :c:func:`Py_IsFinalizing` or :func:`sys.is_finalizing` to
       check if the interpreter is in process of being finalized before calling
       this function to avoid unwanted termination.
 
@@ -898,7 +906,7 @@ with sub-interpreters:
    .. note::
       Calling this function from a thread when the runtime is finalizing
       will terminate the thread, even if the thread was not created by Python.
-      You can use :c:func:`!_Py_IsFinalizing` or :func:`sys.is_finalizing` to
+      You can use :c:func:`Py_IsFinalizing` or :func:`sys.is_finalizing` to
       check if the interpreter is in process of being finalized before calling
       this function to avoid unwanted termination.
 
@@ -1180,7 +1188,7 @@ All of the following functions must be called after :c:func:`Py_Initialize`.
    .. note::
       Calling this function from a thread when the runtime is finalizing
       will terminate the thread, even if the thread was not created by Python.
-      You can use :c:func:`!_Py_IsFinalizing` or :func:`sys.is_finalizing` to
+      You can use :c:func:`Py_IsFinalizing` or :func:`sys.is_finalizing` to
       check if the interpreter is in process of being finalized before calling
       this function to avoid unwanted termination.
 
diff --git a/Doc/library/sys.rst b/Doc/library/sys.rst
index b6346ba..da2435a 100644
--- a/Doc/library/sys.rst
+++ b/Doc/library/sys.rst
@@ -1121,8 +1121,8 @@ always available.
 
 .. function:: is_finalizing()
 
-   Return :const:`True` if the Python interpreter is
-   :term:`shutting down <interpreter shutdown>`, :const:`False` otherwise.
+   Return :const:`True` if the main Python interpreter is
+   :term:`shutting down <interpreter shutdown>`. Return :const:`False` otherwise.
 
    .. versionadded:: 3.5
 
diff --git a/Doc/whatsnew/3.13.rst b/Doc/whatsnew/3.13.rst
index 13ae6e5..85aa81b 100644
--- a/Doc/whatsnew/3.13.rst
+++ b/Doc/whatsnew/3.13.rst
@@ -832,6 +832,10 @@ New Features
   not needed.
   (Contributed by Victor Stinner in :gh:`106004`.)
 
+* Add :c:func:`Py_IsFinalizing` function: check if the main Python interpreter is
+  :term:`shutting down <interpreter shutdown>`.
+  (Contributed by Victor Stinner in :gh:`108014`.)
+
 Porting to Python 3.13
 ----------------------