diff --git a/Doc/library/io.rst b/Doc/library/io.rst index e623a041acf..9738c5c2ad2 100644 --- a/Doc/library/io.rst +++ b/Doc/library/io.rst @@ -226,7 +226,7 @@ I/O Base Classes implementations represent a file that cannot be read, written or seeked. - Even though :class:`IOBase` does not declare :meth:`read`, :meth:`readinto`, + Even though :class:`IOBase` does not declare :meth:`read` or :meth:`write` because their signatures will vary, implementations and clients should consider those methods part of the interface. Also, implementations may raise a :exc:`ValueError` (or :exc:`UnsupportedOperation`) @@ -234,9 +234,7 @@ I/O Base Classes The basic type used for binary data read from or written to a file is :class:`bytes`. Other :term:`bytes-like objects ` are - accepted as method arguments too. In some cases, such as - :meth:`~RawIOBase.readinto`, a writable object such as :class:`bytearray` - is required. Text I/O classes work with :class:`str` data. + accepted as method arguments too. Text I/O classes work with :class:`str` data. Note that calling any method (even inquiries) on a closed stream is undefined. Implementations may raise :exc:`ValueError` in this case. @@ -405,7 +403,8 @@ I/O Base Classes Read bytes into a pre-allocated, writable :term:`bytes-like object` *b*, and return the - number of bytes read. If the object is in non-blocking mode and no bytes + number of bytes read. For example, *b* might be a :class:`bytearray`. + If the object is in non-blocking mode and no bytes are available, ``None`` is returned. .. method:: write(b) @@ -495,6 +494,7 @@ I/O Base Classes Read bytes into a pre-allocated, writable :term:`bytes-like object` *b* and return the number of bytes read. + For example, *b* might be a :class:`bytearray`. Like :meth:`read`, multiple reads may be issued to the underlying raw stream, unless the latter is interactive. @@ -757,8 +757,7 @@ Text I/O .. class:: TextIOBase Base class for text streams. This class provides a character and line based - interface to stream I/O. There is no :meth:`readinto` method because - Python's character strings are immutable. It inherits :class:`IOBase`. + interface to stream I/O. It inherits :class:`IOBase`. There is no public constructor. :class:`TextIOBase` provides or overrides these data attributes and @@ -1048,4 +1047,3 @@ The above implicitly extends to text files, since the :func:`open()` function will wrap a buffered object inside a :class:`TextIOWrapper`. This includes standard streams and therefore affects the built-in function :func:`print()` as well. - diff --git a/Lib/_pyio.py b/Lib/_pyio.py index f0d4f4ed27a..0c0cb84a48e 100644 --- a/Lib/_pyio.py +++ b/Lib/_pyio.py @@ -287,16 +287,15 @@ class IOBase(metaclass=abc.ABCMeta): derived classes can override selectively; the default implementations represent a file that cannot be read, written or seeked. - Even though IOBase does not declare read, readinto, or write because + Even though IOBase does not declare read or write because their signatures will vary, implementations and clients should consider those methods part of the interface. Also, implementations may raise UnsupportedOperation when operations they do not support are called. The basic type used for binary data read from or written to a file is - bytes. Other bytes-like objects are accepted as method arguments too. In - some cases (such as readinto), a writable object is required. Text I/O - classes work with str data. + bytes. Other bytes-like objects are accepted as method arguments too. + Text I/O classes work with str data. Note that calling any method (even inquiries) on a closed stream is undefined. Implementations may raise OSError in this case. @@ -1759,8 +1758,7 @@ class TextIOBase(IOBase): """Base class for text I/O. This class provides a character and line based interface to stream - I/O. There is no readinto method because Python's character strings - are immutable. There is no public constructor. + I/O. There is no public constructor. """ def read(self, size=-1):