gh-96005: Handle WASI ENOTCAPABLE in getpath (GH-96006)

- On WASI `ENOTCAPABLE` is now mapped to `PermissionError`.
- The `errno` modules exposes the new error number.
- `getpath.py` now ignores `PermissionError` when it cannot open landmark
  files `pybuilddir.txt` and `pyenv.cfg`.

2 files changed, 15 insertions, 1 deletions

diff --git a/Doc/library/errno.rst b/Doc/library/errno.rst
index 035340e..da4e964 100644
--- a/Doc/library/errno.rst
+++ b/Doc/library/errno.rst
@@ -657,3 +657,12 @@ defined by the module.  The specific list of defined symbols is available as
    Interface output queue is full
 
    .. versionadded:: 3.11
+
+.. data:: ENOTCAPABLE
+
+   Capabilities insufficient. This error is mapped to the exception
+   :exc:`PermissionError`.
+
+   .. availability:: WASI
+
+   .. versionadded:: 3.11.1
diff --git a/Doc/library/exceptions.rst b/Doc/library/exceptions.rst
index 2eccbd1..fc85627 100644
--- a/Doc/library/exceptions.rst
+++ b/Doc/library/exceptions.rst
@@ -746,7 +746,12 @@ depending on the system error code.
 
    Raised when trying to run an operation without the adequate access
    rights - for example filesystem permissions.
-   Corresponds to :c:data:`errno` :py:data:`~errno.EACCES` and :py:data:`~errno.EPERM`.
+   Corresponds to :c:data:`errno` :py:data:`~errno.EACCES`,
+   :py:data:`~errno.EPERM`, and :py:data:`~errno.ENOTCAPABLE`.
+
+   .. versionchanged:: 3.11.1
+      WASI's :py:data:`~errno.ENOTCAPABLE` is now mapped to
+      :exc:`PermissionError`.
 
 .. exception:: ProcessLookupError