symbian-qemu-0.9.1-12/python-2.6.1/Doc/library/io.rst
author johnathan.white@2718R8BGH51.accenture.com
Mon, 08 Mar 2010 18:45:03 +0000
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parent 1 2fb8b9db1c86
permissions -rw-r--r--
Modify framebuffer and NGA framebuffer to read screen size from board model dtb file. Optimise memory usuage of frame buffer Add example minigui application with hooks to profiler (which writes results to S:\). Modified NGA framebuffer to run its own dfc queue at high priority
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:mod:`io` --- Core tools for working with streams
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=================================================
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.. module:: io
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   :synopsis: Core tools for working with streams.
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.. moduleauthor:: Guido van Rossum <guido@python.org>
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.. moduleauthor:: Mike Verdone <mike.verdone@gmail.com>
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.. moduleauthor:: Mark Russell <mark.russell@zen.co.uk>
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.. sectionauthor:: Benjamin Peterson
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.. versionadded:: 2.6
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The :mod:`io` module provides the Python interfaces to stream handling.  The
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builtin :func:`open` function is defined in this module.
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At the top of the I/O hierarchy is the abstract base class :class:`IOBase`.  It
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defines the basic interface to a stream.  Note, however, that there is no
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seperation between reading and writing to streams; implementations are allowed
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to throw an :exc:`IOError` if they do not support a given operation.
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Extending :class:`IOBase` is :class:`RawIOBase` which deals simply with the
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reading and writing of raw bytes to a stream.  :class:`FileIO` subclasses
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:class:`RawIOBase` to provide an interface to files in the machine's
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file system.
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:class:`BufferedIOBase` deals with buffering on a raw byte stream
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(:class:`RawIOBase`).  Its subclasses, :class:`BufferedWriter`,
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:class:`BufferedReader`, and :class:`BufferedRWPair` buffer streams that are
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readable, writable, and both readable and writable.
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:class:`BufferedRandom` provides a buffered interface to random access
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streams.  :class:`BytesIO` is a simple stream of in-memory bytes.
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Another :class:`IOBase` subclass, :class:`TextIOBase`, deals with
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streams whose bytes represent text, and handles encoding and decoding
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from and to strings. :class:`TextIOWrapper`, which extends it, is a
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buffered text interface to a buffered raw stream
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(:class:`BufferedIOBase`). Finally, :class:`StringIO` is an in-memory
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stream for text.
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Argument names are not part of the specification, and only the arguments of
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:func:`open` are intended to be used as keyword arguments.
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Module Interface
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----------------
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.. data:: DEFAULT_BUFFER_SIZE
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   An int containing the default buffer size used by the module's buffered I/O
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   classes.  :func:`open` uses the file's blksize (as obtained by
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   :func:`os.stat`) if possible.
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.. function:: open(file[, mode[, buffering[, encoding[, errors[, newline[, closefd=True]]]]]])
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   Open *file* and return a stream.  If the file cannot be opened, an
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   :exc:`IOError` is raised.
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   *file* is either a string giving the name (and the path if the file isn't in
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   the current working directory) of the file to be opened or a file
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   descriptor of the file to be opened.  (If a file descriptor is given,
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   for example, from :func:`os.fdopen`, it is closed when the returned
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   I/O object is closed, unless *closefd* is set to ``False``.)
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   *mode* is an optional string that specifies the mode in which the file is
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   opened.  It defaults to ``'r'`` which means open for reading in text mode.
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   Other common values are ``'w'`` for writing (truncating the file if it
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   already exists), and ``'a'`` for appending (which on *some* Unix systems,
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   means that *all* writes append to the end of the file regardless of the
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   current seek position).  In text mode, if *encoding* is not specified the
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   encoding used is platform dependent. (For reading and writing raw bytes use
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   binary mode and leave *encoding* unspecified.)  The available modes are:
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   ========= ===============================================================
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   Character Meaning
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   --------- ---------------------------------------------------------------
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   ``'r'``   open for reading (default)
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   ``'w'``   open for writing, truncating the file first
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   ``'a'``   open for writing, appending to the end of the file if it exists
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   ``'b'``   binary mode
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   ``'t'``   text mode (default)
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   ``'+'``   open a disk file for updating (reading and writing)
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   ``'U'``   universal newline mode (for backwards compatibility; should
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             not be used in new code)
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   ========= ===============================================================
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   The default mode is ``'rt'`` (open for reading text).  For binary random
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   access, the mode ``'w+b'`` opens and truncates the file to 0 bytes, while
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   ``'r+b'`` opens the file without truncation.
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   Python distinguishes between files opened in binary and text modes, even when
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   the underlying operating system doesn't.  Files opened in binary mode
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   (including ``'b'`` in the *mode* argument) return contents as ``bytes``
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   objects without any decoding.  In text mode (the default, or when ``'t'`` is
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   included in the *mode* argument), the contents of the file are returned as
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   strings, the bytes having been first decoded using a platform-dependent
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   encoding or using the specified *encoding* if given.
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   *buffering* is an optional integer used to set the buffering policy.  By
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   default full buffering is on.  Pass 0 to switch buffering off (only allowed
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   in binary mode), 1 to set line buffering, and an integer > 1 for full
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   buffering.
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   *encoding* is the name of the encoding used to decode or encode the file.
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   This should only be used in text mode.  The default encoding is platform
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   dependent, but any encoding supported by Python can be used.  See the
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   :mod:`codecs` module for the list of supported encodings.
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   *errors* is an optional string that specifies how encoding and decoding
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   errors are to be handled.  Pass ``'strict'`` to raise a :exc:`ValueError`
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   exception if there is an encoding error (the default of ``None`` has the same
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   effect), or pass ``'ignore'`` to ignore errors.  (Note that ignoring encoding
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   errors can lead to data loss.)  ``'replace'`` causes a replacement marker
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   (such as ``'?'``) to be inserted where there is malformed data.  When
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   writing, ``'xmlcharrefreplace'`` (replace with the appropriate XML character
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   reference) or ``'backslashreplace'`` (replace with backslashed escape
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   sequences) can be used.  Any other error handling name that has been
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   registered with :func:`codecs.register_error` is also valid.
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   *newline* controls how universal newlines works (it only applies to text
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   mode).  It can be ``None``, ``''``, ``'\n'``, ``'\r'``, and ``'\r\n'``.  It
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   works as follows:
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   * On input, if *newline* is ``None``, universal newlines mode is enabled.
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     Lines in the input can end in ``'\n'``, ``'\r'``, or ``'\r\n'``, and these
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     are translated into ``'\n'`` before being returned to the caller.  If it is
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     ``''``, universal newline mode is enabled, but line endings are returned to
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     the caller untranslated.  If it has any of the other legal values, input
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     lines are only terminated by the given string, and the line ending is
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     returned to the caller untranslated.
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   * On output, if *newline* is ``None``, any ``'\n'`` characters written are
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     translated to the system default line separator, :data:`os.linesep`.  If
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     *newline* is ``''``, no translation takes place.  If *newline* is any of
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     the other legal values, any ``'\n'`` characters written are translated to
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     the given string.
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   If *closefd* is ``False`` and a file descriptor rather than a
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   filename was given, the underlying file descriptor will be kept open
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   when the file is closed.  If a filename is given *closefd* has no
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   effect but must be ``True`` (the default).
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   The type of file object returned by the :func:`open` function depends
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   on the mode.  When :func:`open` is used to open a file in a text mode
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   (``'w'``, ``'r'``, ``'wt'``, ``'rt'``, etc.), it returns a
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   :class:`TextIOWrapper`. When used to open a file in a binary mode,
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   the returned class varies: in read binary mode, it returns a
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   :class:`BufferedReader`; in write binary and append binary modes, it
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   returns a :class:`BufferedWriter`, and in read/write mode, it returns
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   a :class:`BufferedRandom`.
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   It is also possible to use a string or bytearray as a file for both reading
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   and writing.  For strings :class:`StringIO` can be used like a file opened in
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   a text mode, and for bytearrays a :class:`BytesIO` can be used like a
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   file opened in a binary mode.
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.. exception:: BlockingIOError
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   Error raised when blocking would occur on a non-blocking stream.  It inherits
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   :exc:`IOError`.
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   In addition to those of :exc:`IOError`, :exc:`BlockingIOError` has one
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   attribute:
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   .. attribute:: characters_written
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      An integer containing the number of characters written to the stream
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      before it blocked.
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   168
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.. exception:: UnsupportedOperation
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   171
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   An exception inheriting :exc:`IOError` and :exc:`ValueError` that is raised
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   when an unsupported operation is called on a stream.
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   174
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   175
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   176
I/O Base Classes
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----------------
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.. class:: IOBase
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   The abstract base class for all I/O classes, acting on streams of bytes.
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   There is no public constructor.
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   183
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   This class provides empty abstract implementations for many methods
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   that derived classes can override selectively; the default
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   186
   implementations represent a file that cannot be read, written or
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   187
   seeked.
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   188
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   189
   Even though :class:`IOBase` does not declare :meth:`read`, :meth:`readinto`,
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   190
   or :meth:`write` because their signatures will vary, implementations and
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   191
   clients should consider those methods part of the interface.  Also,
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   192
   implementations may raise a :exc:`IOError` when operations they do not
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   193
   support are called.
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   194
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   195
   The basic type used for binary data read from or written to a file is
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   196
   :class:`bytes`.  :class:`bytearray`\s are accepted too, and in some cases
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   197
   (such as :class:`readinto`) required.  Text I/O classes work with
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   198
   :class:`str` data.
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   199
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   Note that calling any method (even inquiries) on a closed stream is
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   undefined.  Implementations may raise :exc:`IOError` in this case.
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   202
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   IOBase (and its subclasses) support the iterator protocol, meaning that an
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   204
   :class:`IOBase` object can be iterated over yielding the lines in a stream.
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   205
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   IOBase is also a context manager and therefore supports the
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   :keyword:`with` statement.  In this example, *file* is closed after the
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   :keyword:`with` statement's suite is finished---even if an exception occurs::
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      with open('spam.txt', 'w') as file:
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          file.write('Spam and eggs!')
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   212
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   213
   :class:`IOBase` provides these data attributes and methods:
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   .. method:: close()
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      Flush and close this stream.  This method has no effect if the file is
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      already closed.
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   .. attribute:: closed
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   221
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      True if the stream is closed.
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   224
   .. method:: fileno()
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      Return the underlying file descriptor (an integer) of the stream if it
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      exists.  An :exc:`IOError` is raised if the IO object does not use a file
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      descriptor.
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   229
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   230
   .. method:: flush()
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   231
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   232
      Flush the write buffers of the stream if applicable.  This does nothing
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   233
      for read-only and non-blocking streams.
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   234
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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   235
   .. method:: isatty()
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   236
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   237
      Return ``True`` if the stream is interactive (i.e., connected to
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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   238
      a terminal/tty device).
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   239
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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   240
   .. method:: readable()
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   241
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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   242
      Return ``True`` if the stream can be read from.  If False, :meth:`read`
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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   243
      will raise :exc:`IOError`.
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   244
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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   245
   .. method:: readline([limit])
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   246
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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   247
      Read and return one line from the stream.  If *limit* is specified, at
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   248
      most *limit* bytes will be read.
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   249
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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   250
      The line terminator is always ``b'\n'`` for binary files; for text files,
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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   251
      the *newlines* argument to :func:`open` can be used to select the line
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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   252
      terminator(s) recognized.
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   253
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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   254
   .. method:: readlines([hint])
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   255
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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   256
      Read and return a list of lines from the stream.  *hint* can be specified
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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   257
      to control the number of lines read: no more lines will be read if the
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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   258
      total size (in bytes/characters) of all lines so far exceeds *hint*.
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   259
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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   260
   .. method:: seek(offset[, whence])
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   261
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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   262
      Change the stream position to the given byte *offset*.  *offset* is
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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   263
      interpreted relative to the position indicated by *whence*.  Values for
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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   264
      *whence* are:
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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diff changeset
   265
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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   266
      * ``0`` -- start of the stream (the default); *offset* should be zero or positive
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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   267
      * ``1`` -- current stream position; *offset* may be negative
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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   268
      * ``2`` -- end of the stream; *offset* is usually negative
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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diff changeset
   269
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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   270
      Return the new absolute position.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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   271
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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   272
   .. method:: seekable()
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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   273
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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   274
      Return ``True`` if the stream supports random access.  If ``False``,
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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   275
      :meth:`seek`, :meth:`tell` and :meth:`truncate` will raise :exc:`IOError`.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff changeset
   276
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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   277
   .. method:: tell()
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff changeset
   278
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff changeset
   279
      Return the current stream position.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff changeset
   280
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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diff changeset
   281
   .. method:: truncate([size])
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff changeset
   282
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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diff changeset
   283
      Truncate the file to at most *size* bytes.  *size* defaults to the current
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff changeset
   284
      file position, as returned by :meth:`tell`.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff changeset
   285
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff changeset
   286
   .. method:: writable()
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff changeset
   287
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff changeset
   288
      Return ``True`` if the stream supports writing.  If ``False``,
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   289
      :meth:`write` and :meth:`truncate` will raise :exc:`IOError`.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   290
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff changeset
   291
   .. method:: writelines(lines)
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff changeset
   292
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff changeset
   293
      Write a list of lines to the stream.  Line separators are not added, so it
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   294
      is usual for each of the lines provided to have a line separator at the
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   295
      end.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   296
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff changeset
   297
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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diff changeset
   298
.. class:: RawIOBase
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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diff changeset
   299
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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diff changeset
   300
   Base class for raw binary I/O.  It inherits :class:`IOBase`.  There is no
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   301
   public constructor.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   302
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff changeset
   303
   In addition to the attributes and methods from :class:`IOBase`,
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   304
   RawIOBase provides the following methods:
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff changeset
   305
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff changeset
   306
   .. method:: read([n])
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff changeset
   307
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff changeset
   308
      Read and return all the bytes from the stream until EOF, or if *n* is
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   309
      specified, up to *n* bytes.  Only one system call is ever made.  An empty
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   310
      bytes object is returned on EOF; ``None`` is returned if the object is set
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   311
      not to block and has no data to read.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   312
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff changeset
   313
   .. method:: readall()
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff changeset
   314
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   315
      Read and return all the bytes from the stream until EOF, using multiple
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   316
      calls to the stream if necessary.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   317
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff changeset
   318
   .. method:: readinto(b)
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff changeset
   319
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   320
      Read up to len(b) bytes into bytearray *b* and return the number of bytes
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   321
      read.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   322
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff changeset
   323
   .. method:: write(b)
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   324
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   325
      Write the given bytes or bytearray object, *b*, to the underlying raw
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   326
      stream and return the number of bytes written (This is never less than
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   327
      ``len(b)``, since if the write fails, an :exc:`IOError` will be raised).
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   328
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   329
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   330
Raw File I/O
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   331
------------
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   332
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff changeset
   333
.. class:: FileIO(name[, mode])
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff changeset
   334
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   335
   :class:`FileIO` represents a file containing bytes data.  It implements
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   336
   the :class:`RawIOBase` interface (and therefore the :class:`IOBase`
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   337
   interface, too).
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   338
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff changeset
   339
   The *mode* can be ``'r'``, ``'w'`` or ``'a'`` for reading (default), writing,
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   340
   or appending.  The file will be created if it doesn't exist when opened for
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   341
   writing or appending; it will be truncated when opened for writing.  Add a
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   342
   ``'+'`` to the mode to allow simultaneous reading and writing.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   343
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   344
   In addition to the attributes and methods from :class:`IOBase` and
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   345
   :class:`RawIOBase`, :class:`FileIO` provides the following data
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   346
   attributes and methods:
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   347
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   348
   .. attribute:: mode
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff changeset
   349
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff changeset
   350
      The mode as given in the constructor.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff changeset
   351
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff changeset
   352
   .. attribute:: name
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff changeset
   353
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   354
      The file name.  This is the file descriptor of the file when no name is
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   355
      given in the constructor.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   356
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   357
   .. method:: read([n])
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   358
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   359
      Read and return at most *n* bytes.  Only one system call is made, so it is
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   360
      possible that less data than was requested is returned.  Use :func:`len`
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   361
      on the returned bytes object to see how many bytes were actually returned.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   362
      (In non-blocking mode, ``None`` is returned when no data is available.)
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   363
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   364
   .. method:: readall()
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   365
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   366
      Read and return the entire file's contents in a single bytes object.  As
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   367
      much as immediately available is returned in non-blocking mode.  If the
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   368
      EOF has been reached, ``b''`` is returned.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   369
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   370
   .. method:: write(b)
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   371
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   372
      Write the bytes or bytearray object, *b*, to the file, and return
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   373
      the number actually written. Only one system call is made, so it
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   374
      is possible that only some of the data is written.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   375
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   376
   Note that the inherited ``readinto()`` method should not be used on
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   377
   :class:`FileIO` objects.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   378
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   379
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   380
Buffered Streams
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   381
----------------
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   382
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   383
.. class:: BufferedIOBase
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   384
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   385
   Base class for streams that support buffering.  It inherits :class:`IOBase`.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   386
   There is no public constructor.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   387
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   388
   The main difference with :class:`RawIOBase` is that the :meth:`read` method
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   389
   supports omitting the *size* argument, and does not have a default
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   390
   implementation that defers to :meth:`readinto`.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   391
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   392
   In addition, :meth:`read`, :meth:`readinto`, and :meth:`write` may raise
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   393
   :exc:`BlockingIOError` if the underlying raw stream is in non-blocking mode
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   394
   and not ready; unlike their raw counterparts, they will never return
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   395
   ``None``.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   396
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   397
   A typical implementation should not inherit from a :class:`RawIOBase`
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   398
   implementation, but wrap one like :class:`BufferedWriter` and
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   399
   :class:`BufferedReader`.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   400
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   401
   :class:`BufferedIOBase` provides or overrides these methods in addition to
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   402
   those from :class:`IOBase`:
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   403
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   404
   .. method:: read([n])
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   405
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   406
      Read and return up to *n* bytes.  If the argument is omitted, ``None``, or
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   407
      negative, data is read and returned until EOF is reached.  An empty bytes
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   408
      object is returned if the stream is already at EOF.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   409
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   410
      If the argument is positive, and the underlying raw stream is not
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   411
      interactive, multiple raw reads may be issued to satisfy the byte count
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   412
      (unless EOF is reached first).  But for interactive raw streams, at most
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   413
      one raw read will be issued, and a short result does not imply that EOF is
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   414
      imminent.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   415
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   416
      A :exc:`BlockingIOError` is raised if the underlying raw stream has no
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   417
      data at the moment.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   418
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   419
   .. method:: readinto(b)
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   420
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   421
      Read up to len(b) bytes into bytearray *b* and return the number of bytes
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   422
      read.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   423
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   424
      Like :meth:`read`, multiple reads may be issued to the underlying raw
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   425
      stream, unless the latter is 'interactive.'
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   426
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   427
      A :exc:`BlockingIOError` is raised if the underlying raw stream has no
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   428
      data at the moment.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   429
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   430
   .. method:: write(b)
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   431
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   432
      Write the given bytes or bytearray object, *b*, to the underlying raw
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   433
      stream and return the number of bytes written (never less than ``len(b)``,
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   434
      since if the write fails an :exc:`IOError` will be raised).
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   435
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   436
      A :exc:`BlockingIOError` is raised if the buffer is full, and the
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   437
      underlying raw stream cannot accept more data at the moment.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   438
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   439
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   440
.. class:: BytesIO([initial_bytes])
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   441
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   442
   A stream implementation using an in-memory bytes buffer.  It inherits
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   443
   :class:`BufferedIOBase`.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   444
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   445
   The argument *initial_bytes* is an optional initial bytearray.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   446
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   447
   :class:`BytesIO` provides or overrides these methods in addition to those
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   448
   from :class:`BufferedIOBase` and :class:`IOBase`:
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   449
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   450
   .. method:: getvalue()
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   451
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   452
      Return ``bytes`` containing the entire contents of the buffer.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   453
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   454
   .. method:: read1()
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   455
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   456
      In :class:`BytesIO`, this is the same as :meth:`read`.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   457
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   458
   .. method:: truncate([size])
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   459
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   460
      Truncate the buffer to at most *size* bytes.  *size* defaults to the
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   461
      current stream position, as returned by :meth:`tell`.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   462
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   463
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   464
.. class:: BufferedReader(raw[, buffer_size])
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   465
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   466
   A buffer for a readable, sequential :class:`RawIOBase` object.  It inherits
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   467
   :class:`BufferedIOBase`.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   468
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   469
   The constructor creates a :class:`BufferedReader` for the given readable
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   470
   *raw* stream and *buffer_size*.  If *buffer_size* is omitted,
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   471
   :data:`DEFAULT_BUFFER_SIZE` is used.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   472
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   473
   :class:`BufferedReader` provides or overrides these methods in addition to
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   474
   those from :class:`BufferedIOBase` and :class:`IOBase`:
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   475
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   476
   .. method:: peek([n])
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   477
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   478
      Return 1 (or *n* if specified) bytes from a buffer without advancing the
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   479
      position.  Only a single read on the raw stream is done to satisfy the
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   480
      call. The number of bytes returned may be less than requested since at
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   481
      most all the buffer's bytes from the current position to the end are
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   482
      returned.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   483
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   484
   .. method:: read([n])
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   485
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   486
      Read and return *n* bytes, or if *n* is not given or negative, until EOF
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   487
      or if the read call would block in non-blocking mode.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   488
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   489
   .. method:: read1(n)
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   490
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   491
      Read and return up to *n* bytes with only one call on the raw stream.  If
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   492
      at least one byte is buffered, only buffered bytes are returned.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   493
      Otherwise, one raw stream read call is made.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   494
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   495
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   496
.. class:: BufferedWriter(raw[, buffer_size[, max_buffer_size]])
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   497
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   498
   A buffer for a writeable sequential RawIO object.  It inherits
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   499
   :class:`BufferedIOBase`.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   500
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   501
   The constructor creates a :class:`BufferedWriter` for the given writeable
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   502
   *raw* stream.  If the *buffer_size* is not given, it defaults to
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   503
   :data:`DEAFULT_BUFFER_SIZE`.  If *max_buffer_size* is omitted, it defaults to
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   504
   twice the buffer size.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   505
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   506
   :class:`BufferedWriter` provides or overrides these methods in addition to
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   507
   those from :class:`BufferedIOBase` and :class:`IOBase`:
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   508
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   509
   .. method:: flush()
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   510
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   511
      Force bytes held in the buffer into the raw stream.  A
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   512
      :exc:`BlockingIOError` should be raised if the raw stream blocks.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   513
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   514
   .. method:: write(b)
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   515
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   516
      Write the bytes or bytearray object, *b*, onto the raw stream and return
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   517
      the number of bytes written.  A :exc:`BlockingIOError` is raised when the
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   518
      raw stream blocks.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   519
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   520
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   521
.. class:: BufferedRWPair(reader, writer[, buffer_size[, max_buffer_size]])
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   522
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   523
   A combined buffered writer and reader object for a raw stream that can be
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   524
   written to and read from.  It has and supports both :meth:`read`, :meth:`write`,
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   525
   and their variants.  This is useful for sockets and two-way pipes.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   526
   It inherits :class:`BufferedIOBase`.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   527
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   528
   *reader* and *writer* are :class:`RawIOBase` objects that are readable and
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   529
   writeable respectively.  If the *buffer_size* is omitted it defaults to
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   530
   :data:`DEFAULT_BUFFER_SIZE`.  The *max_buffer_size* (for the buffered writer)
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   531
   defaults to twice the buffer size.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   532
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   533
   :class:`BufferedRWPair` implements all of :class:`BufferedIOBase`\'s methods.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   534
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   535
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   536
.. class:: BufferedRandom(raw[, buffer_size[, max_buffer_size]])
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   537
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   538
   A buffered interface to random access streams.  It inherits
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   539
   :class:`BufferedReader` and :class:`BufferedWriter`.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   540
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   541
   The constructor creates a reader and writer for a seekable raw stream, given
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   542
   in the first argument.  If the *buffer_size* is omitted it defaults to
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   543
   :data:`DEFAULT_BUFFER_SIZE`.  The *max_buffer_size* (for the buffered writer)
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   544
   defaults to twice the buffer size.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   545
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   546
   :class:`BufferedRandom` is capable of anything :class:`BufferedReader` or
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   547
   :class:`BufferedWriter` can do.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   548
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   549
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   550
Text I/O
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   551
--------
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   552
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   553
.. class:: TextIOBase
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   554
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   555
   Base class for text streams.  This class provides a character and line based
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   556
   interface to stream I/O.  There is no :meth:`readinto` method because
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   557
   Python's character strings are immutable.  It inherits :class:`IOBase`.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   558
   There is no public constructor.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   559
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   560
   :class:`TextIOBase` provides or overrides these data attributes and
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   561
   methods in addition to those from :class:`IOBase`:
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   562
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   563
   .. attribute:: encoding
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   564
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   565
      The name of the encoding used to decode the stream's bytes into
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   566
      strings, and to encode strings into bytes.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   567
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   568
   .. attribute:: newlines
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   569
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   570
      A string, a tuple of strings, or ``None``, indicating the newlines
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   571
      translated so far.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   572
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   573
   .. method:: read(n)
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   574
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   575
      Read and return at most *n* characters from the stream as a single
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   576
      :class:`str`.  If *n* is negative or ``None``, reads to EOF.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   577
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   578
   .. method:: readline()
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   579
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   580
      Read until newline or EOF and return a single ``str``.  If the stream is
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   581
      already at EOF, an empty string is returned.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   582
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   583
   .. method:: write(s)
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   584
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   585
      Write the string *s* to the stream and return the number of characters
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   586
      written.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   587
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   588
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   589
.. class:: TextIOWrapper(buffer[, encoding[, errors[, newline[, line_buffering]]]])
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   590
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   591
   A buffered text stream over a :class:`BufferedIOBase` raw stream, *buffer*.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   592
   It inherits :class:`TextIOBase`.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   593
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   594
   *encoding* gives the name of the encoding that the stream will be decoded or
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   595
   encoded with.  It defaults to :func:`locale.getpreferredencoding`.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   596
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   597
   *errors* is an optional string that specifies how encoding and decoding
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   598
   errors are to be handled.  Pass ``'strict'`` to raise a :exc:`ValueError`
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   599
   exception if there is an encoding error (the default of ``None`` has the same
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   600
   effect), or pass ``'ignore'`` to ignore errors.  (Note that ignoring encoding
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   601
   errors can lead to data loss.)  ``'replace'`` causes a replacement marker
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   602
   (such as ``'?'``) to be inserted where there is malformed data.  When
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   603
   writing, ``'xmlcharrefreplace'`` (replace with the appropriate XML character
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   604
   reference) or ``'backslashreplace'`` (replace with backslashed escape
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   605
   sequences) can be used.  Any other error handling name that has been
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   606
   registered with :func:`codecs.register_error` is also valid.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   607
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   608
   *newline* can be ``None``, ``''``, ``'\n'``, ``'\r'``, or ``'\r\n'``.  It
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   609
   controls the handling of line endings.  If it is ``None``, universal newlines
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   610
   is enabled.  With this enabled, on input, the lines endings ``'\n'``,
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   611
   ``'\r'``, or ``'\r\n'`` are translated to ``'\n'`` before being returned to
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   612
   the caller.  Conversely, on output, ``'\n'`` is translated to the system
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   613
   default line seperator, :data:`os.linesep`.  If *newline* is any other of its
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   614
   legal values, that newline becomes the newline when the file is read and it
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   615
   is returned untranslated.  On output, ``'\n'`` is converted to the *newline*.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   616
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   617
   If *line_buffering* is ``True``, :meth:`flush` is implied when a call to
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   618
   write contains a newline character.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   619
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   620
   :class:`TextIOWrapper` provides these data attributes in addition to those of
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   621
   :class:`TextIOBase` and its parents:
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   622
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   623
   .. attribute:: errors
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   624
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   625
      The encoding and decoding error setting.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   626
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   627
   .. attribute:: line_buffering
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   628
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   629
      Whether line buffering is enabled.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   630
   
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   631
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   632
.. class:: StringIO([initial_value[, encoding[, errors[, newline]]]])
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   633
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   634
   An in-memory stream for text.  It in inherits :class:`TextIOWrapper`.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   635
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   636
   Create a new StringIO stream with an inital value, encoding, error handling,
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   637
   and newline setting.  See :class:`TextIOWrapper`\'s constructor for more
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   638
   information.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   639
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   640
   :class:`StringIO` provides this method in addition to those from
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   641
   :class:`TextIOWrapper` and its parents:
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   642
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   643
   .. method:: getvalue()
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   644
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   645
      Return a ``str`` containing the entire contents of the buffer.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   646
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   647
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   648
.. class:: IncrementalNewlineDecoder
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   649
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   650
   A helper codec that decodes newlines for universal newlines mode.  It
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   651
   inherits :class:`codecs.IncrementalDecoder`.
2fb8b9db1c86 Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff changeset
   652