file :: Class file

Class file

object --+
         |
        file

file(name[, mode[, buffering]]) -> file object

Open a file. The mode can be 'r', 'w' or 'a' for reading (default), writing or appending. The file will be created if it doesn't exist when opened for writing or appending; it will be truncated when opened for writing. Add a 'b' to the mode for binary files. Add a '+' to the mode to allow simultaneous reading and writing. If the buffering argument is given, 0 means unbuffered, 1 means line buffered, and larger numbers specify the buffer size. The preferred way to open a file is with the builtin open() function. Add a 'U' to mode to open the file for input with universal newline support. Any line ending in the input file will be seen as a 'n' in Python. Also, a file so opened gains the attribute 'newlines'; the value for this attribute is one of None (no newline read yet), 'r', 'n', 'rn' or a tuple containing all the newline types seen.

'U' cannot be combined with 'w' or '+' mode.

Instance Methods

[hide private]

__delattr__(...)
x.__delattr__('name') <==> del x.name

self.

__enter__()

None

__exit__(*excinfo)
Closes the file.

__getattribute__(...)
x.__getattribute__('name') <==> x.name

file object

__init__(name, mode=..., buffering=...)
x.__init__(...) initializes x; see help(type(x)) for signature

__iter__(x)
iter(x)

a new object with type S, a subtype of T

__new__(T, S, ...)

__repr__(x)
repr(x)

__setattr__(...)
x.__setattr__('name', value) <==> x.name = value

None or (perhaps) an integer

close()
Close the file.

integer "file descriptor"

fileno()
This is needed for lower-level file interfaces, such os.read().

None

flush()
Flush the internal I/O buffer.

true or false

isatty()
True if the file is connected to a tty device.

the next value, or raise StopIteration

next(x)

read at most size bytes, returned as a string

read(size=...)
If the size argument is negative or omitted, read until EOF is reached. Notice that when in non-blocking mode, less data than what was requested may be returned, even if no size parameter was given.

Undocumented

readinto()
Don't use this; it may go away.

next line from the file, as a string

readline(size=...)
Retain newline. A non-negative size argument limits the maximum number of bytes to return (an incomplete line may be returned then). Return an empty string at EOF.

list of strings, each a line from the file

readlines(size=...)
Call readline() repeatedly and return a list of the lines so read. The optional size argument, if given, is an approximate bound on the total number of bytes in the lines returned.

None

seek(offset, whence=...)
Move to new file position.

current file position, an integer (may be a long integer).

tell()

None

truncate(size=...)
Truncate the file to at most size bytes.

None

write(str)
Write string str to file.

None

writelines(sequence_of_strings)
Write the strings to the file.

returns self

xreadlines()
For backward compatibility. File objects now include the performance optimizations previously implemented in the xreadlines module.

Inherited from object: __format__, __hash__, __reduce__, __reduce_ex__, __sizeof__, __str__, __subclasshook__

Properties

[hide private]

closed
True if the file is closed

encoding
file encoding

errors
Unicode error handler

mode
file mode ('r', 'U', 'w', 'a', possibly with 'b' or '+' added)

name
file name

newlines
end-of-line convention used in this file

softspace
flag indicating that a space needs to be printed; used by print

Inherited from object: __class__

Method Details

[hide private]

delattr(...)

x.__delattr__('name') <==> del x.name

Overrides: object.__delattr__

getattribute(...)

x.__getattribute__('name') <==> x.name

Overrides: object.__getattribute__

init(name, mode=..., buffering=...)
(Constructor)

x.__init__(...) initializes x; see help(type(x)) for signature

Returns: file object
Overrides: object.__init__

new(T, S, ...)

Returns: a new object with type S, a subtype of T
Overrides: object.__new__

repr(x)
(Representation operator)

repr(x)

Overrides: object.__repr__

setattr(...)

x.__setattr__('name', value) <==> x.name = value

Overrides: object.__setattr__

close()

Close the file.

Sets data attribute .closed to True. A closed file cannot be used for further I/O operations. close() may be called more than once without error. Some kinds of file objects (for example, opened by popen()) may return an exit status upon closing.

Returns: None or (perhaps) an integer

seek(offset, whence=...)

Move to new file position.

Argument offset is a byte count. Optional argument whence defaults to 0 (offset from start of file, offset should be >= 0); other values are 1 (move relative to current position, positive or negative), and 2 (move relative to end of file, usually negative, although many platforms allow seeking beyond the end of a file). If the file is opened in text mode, only offsets returned by tell() are legal. Use of other offsets causes undefined behavior. Note that not all file objects are seekable.

Returns: None

truncate(size=...)

Truncate the file to at most size bytes.

Size defaults to the current file position, as returned by tell().

Returns: None

write(str)

Write string str to file.

Note that due to buffering, flush() or close() may be needed before the file on disk reflects the data written.

Returns: None

writelines(sequence_of_strings)

Write the strings to the file.

Note that newlines are not added. The sequence can be any iterable object producing strings. This is equivalent to calling write() for each string.

Returns: None

Class file

__delattr__(...)

__getattribute__(...)

__init__(name, mode=..., buffering=...) (Constructor)

__new__(T, S, ...)

__repr__(x) (Representation operator)

__setattr__(...)

close()

seek(offset, whence=...)

truncate(size=...)

write(str)

writelines(sequence_of_strings)

delattr(...)

getattribute(...)

init(name, mode=..., buffering=...)
(Constructor)

new(T, S, ...)

repr(x)
(Representation operator)

setattr(...)