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+.. highlightlang:: c
+
+.. _fileobjects:
+
+File Objects
+------------
+
+.. index:: object: file
+
+Python's built-in file objects are implemented entirely on the :ctype:`FILE\*`
+support from the C standard library. This is an implementation detail and may
+change in future releases of Python.
+
+
+.. ctype:: PyFileObject
+
+ This subtype of :ctype:`PyObject` represents a Python file object.
+
+
+.. cvar:: PyTypeObject PyFile_Type
+
+ .. index:: single: FileType (in module types)
+
+ This instance of :ctype:`PyTypeObject` represents the Python file type. This is
+ exposed to Python programs as ``file`` and ``types.FileType``.
+
+
+.. cfunction:: int PyFile_Check(PyObject *p)
+
+ Return true if its argument is a :ctype:`PyFileObject` or a subtype of
+ :ctype:`PyFileObject`.
+
+
+.. cfunction:: int PyFile_CheckExact(PyObject *p)
+
+ Return true if its argument is a :ctype:`PyFileObject`, but not a subtype of
+ :ctype:`PyFileObject`.
+
+
+.. cfunction:: PyFile_FromFd(int fd, char *name, char *mode, int buffering, char *encoding, char *newline, int closefd)
+
+ Create a new :ctype:`PyFileObject` from the file descriptor of an already
+ opened file *fd*. The arguments *name*, *encoding* and *newline* can be
+ *NULL* to use the defaults; *buffering* can be *-1* to use the default.
+ Return *NULL* on failure.
+
+ .. warning::
+
+ Take care when you are mixing streams and descriptors! For more
+ information, see `the GNU C Library docs
+ <http://www.gnu.org/software/libc/manual/html_node/Stream_002fDescriptor-Precautions.html#Stream_002fDescriptor-Precautions>`_.
+
+
+.. cfunction:: int PyObject_AsFileDescriptor(PyObject *p)
+
+ Return the file descriptor associated with *p* as an :ctype:`int`. If the
+ object is an integer, its value is returned. If not, the
+ object's :meth:`fileno` method is called if it exists; the method must return
+ an integer, which is returned as the file descriptor value. Sets an
+ exception and returns ``-1`` on failure.
+
+
+.. cfunction:: PyObject* PyFile_GetLine(PyObject *p, int n)
+
+ .. index:: single: EOFError (built-in exception)
+
+ Equivalent to ``p.readline([n])``, this function reads one line from the
+ object *p*. *p* may be a file object or any object with a :meth:`readline`
+ method. If *n* is ``0``, exactly one line is read, regardless of the length of
+ the line. If *n* is greater than ``0``, no more than *n* bytes will be read
+ from the file; a partial line can be returned. In both cases, an empty string
+ is returned if the end of the file is reached immediately. If *n* is less than
+ ``0``, however, one line is read regardless of length, but :exc:`EOFError` is
+ raised if the end of the file is reached immediately.
+
+
+.. cfunction:: PyObject* PyFile_Name(PyObject *p)
+
+ Return the name of the file specified by *p* as a string object.
+
+
+.. cfunction:: void PyFile_SetBufSize(PyFileObject *p, int n)
+
+ .. index:: single: setvbuf()
+
+ Available on systems with :cfunc:`setvbuf` only. This should only be called
+ immediately after file object creation.
+
+
+.. cfunction:: int PyFile_SetEncoding(PyFileObject *p, const char *enc)
+
+ Set the file's encoding for Unicode output to *enc*. Return 1 on success and 0
+ on failure.
+
+
+.. cfunction:: int PyFile_SoftSpace(PyObject *p, int newflag)
+
+ .. index:: single: softspace (file attribute)
+
+ This function exists for internal use by the interpreter. Set the
+ :attr:`softspace` attribute of *p* to *newflag* and return the previous value.
+ *p* does not have to be a file object for this function to work properly; any
+ object is supported (thought its only interesting if the :attr:`softspace`
+ attribute can be set). This function clears any errors, and will return ``0``
+ as the previous value if the attribute either does not exist or if there were
+ errors in retrieving it. There is no way to detect errors from this function,
+ but doing so should not be needed.
+
+
+.. cfunction:: int PyFile_WriteObject(PyObject *obj, PyObject *p, int flags)
+
+ .. index:: single: Py_PRINT_RAW
+
+ Write object *obj* to file object *p*. The only supported flag for *flags* is
+ :const:`Py_PRINT_RAW`; if given, the :func:`str` of the object is written
+ instead of the :func:`repr`. Return ``0`` on success or ``-1`` on failure; the
+ appropriate exception will be set.
+
+
+.. cfunction:: int PyFile_WriteString(const char *s, PyObject *p)
+
+ Write string *s* to file object *p*. Return ``0`` on success or ``-1`` on
+ failure; the appropriate exception will be set.