Issue #12760: Add a create mode to open(). Patch by David Townshend.

1 files changed, 8 insertions, 4 deletions

diff --git a/Doc/library/io.rst b/Doc/library/io.rst
index 85e8c5b..82969eb 100644
--- a/Doc/library/io.rst
+++ b/Doc/library/io.rst
@@ -471,10 +471,13 @@ Raw File I/O
    * an integer representing the number of an existing OS-level file descriptor
      to which the resulting :class:`FileIO` object will give access.
 
-   The *mode* can be ``'r'``, ``'w'`` or ``'a'`` for reading (default), writing,
-   or appending.  The file will be created if it doesn't exist when opened for
-   writing or appending; it will be truncated when opened for writing.  Add a
-   ``'+'`` to the mode to allow simultaneous reading and writing.
+   The *mode* can be ``'r'``, ``'w'``, ``'x'`` or ``'a'`` for reading
+   (default), writing, creating or appending. The file will be created if it
+   doesn't exist when opened for writing or appending; it will be truncated
+   when opened for writing. :exc:`FileExistsError` will be raised if it already
+   exists when opened for creating. Opening a file for creating implies
+   writing, so this mode behaves in a similar way to ``'w'``. Add a ``'+'`` to
+   the mode to allow simultaneous reading and writing.
 
    The :meth:`read` (when called with a positive argument), :meth:`readinto`
    and :meth:`write` methods on this class will only make one system call.
@@ -487,6 +490,7 @@ Raw File I/O
 
    .. versionchanged:: 3.3
       The *opener* parameter was added.
+      The ``'x'`` mode was added.
 
    In addition to the attributes and methods from :class:`IOBase` and
    :class:`RawIOBase`, :class:`FileIO` provides the following data