1 | """The io module provides the Python interfaces to stream handling. The |
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2 | builtin open function is defined in this module. |
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3 | |
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4 | At the top of the I/O hierarchy is the abstract base class IOBase. It |
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5 | defines the basic interface to a stream. Note, however, that there is no |
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6 | separation between reading and writing to streams; implementations are |
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7 | allowed to raise an IOError if they do not support a given operation. |
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8 | |
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9 | Extending IOBase is RawIOBase which deals simply with the reading and |
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10 | writing of raw bytes to a stream. FileIO subclasses RawIOBase to provide |
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11 | an interface to OS files. |
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12 | |
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13 | BufferedIOBase deals with buffering on a raw byte stream (RawIOBase). Its |
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14 | subclasses, BufferedWriter, BufferedReader, and BufferedRWPair buffer |
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15 | streams that are readable, writable, and both respectively. |
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16 | BufferedRandom provides a buffered interface to random access |
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17 | streams. BytesIO is a simple stream of in-memory bytes. |
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18 | |
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19 | Another IOBase subclass, TextIOBase, deals with the encoding and decoding |
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20 | of streams into text. TextIOWrapper, which extends it, is a buffered text |
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21 | interface to a buffered raw stream (`BufferedIOBase`). Finally, StringIO |
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22 | is a in-memory stream for text. |
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23 | |
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24 | Argument names are not part of the specification, and only the arguments |
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25 | of open() are intended to be used as keyword arguments. |
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26 | |
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27 | data: |
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28 | |
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29 | DEFAULT_BUFFER_SIZE |
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30 | |
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31 | An int containing the default buffer size used by the module's buffered |
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32 | I/O classes. open() uses the file's blksize (as obtained by os.stat) if |
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33 | possible. |
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34 | """ |
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35 | # New I/O library conforming to PEP 3116. |
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36 | |
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37 | __author__ = ("Guido van Rossum <guido@python.org>, " |
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38 | "Mike Verdone <mike.verdone@gmail.com>, " |
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39 | "Mark Russell <mark.russell@zen.co.uk>, " |
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40 | "Antoine Pitrou <solipsis@pitrou.net>, " |
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41 | "Amaury Forgeot d'Arc <amauryfa@gmail.com>, " |
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42 | "Benjamin Peterson <benjamin@python.org>") |
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43 | |
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44 | __all__ = ["BlockingIOError", "open", "IOBase", "RawIOBase", "FileIO", |
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45 | "BytesIO", "StringIO", "BufferedIOBase", |
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46 | "BufferedReader", "BufferedWriter", "BufferedRWPair", |
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47 | "BufferedRandom", "TextIOBase", "TextIOWrapper", |
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48 | "UnsupportedOperation", "SEEK_SET", "SEEK_CUR", "SEEK_END"] |
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49 | |
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50 | |
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51 | import _io |
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52 | import abc |
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53 | |
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54 | from _io import (DEFAULT_BUFFER_SIZE, BlockingIOError, UnsupportedOperation, |
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55 | open, FileIO, BytesIO, StringIO, BufferedReader, |
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56 | BufferedWriter, BufferedRWPair, BufferedRandom, |
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57 | IncrementalNewlineDecoder, TextIOWrapper) |
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58 | |
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59 | OpenWrapper = _io.open # for compatibility with _pyio |
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60 | |
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61 | # for seek() |
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62 | SEEK_SET = 0 |
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63 | SEEK_CUR = 1 |
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64 | SEEK_END = 2 |
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65 | |
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66 | # Declaring ABCs in C is tricky so we do it here. |
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67 | # Method descriptions and default implementations are inherited from the C |
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68 | # version however. |
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69 | class IOBase(_io._IOBase): |
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70 | __metaclass__ = abc.ABCMeta |
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71 | __doc__ = _io._IOBase.__doc__ |
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72 | |
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73 | class RawIOBase(_io._RawIOBase, IOBase): |
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74 | __doc__ = _io._RawIOBase.__doc__ |
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75 | |
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76 | class BufferedIOBase(_io._BufferedIOBase, IOBase): |
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77 | __doc__ = _io._BufferedIOBase.__doc__ |
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78 | |
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79 | class TextIOBase(_io._TextIOBase, IOBase): |
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80 | __doc__ = _io._TextIOBase.__doc__ |
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81 | |
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82 | RawIOBase.register(FileIO) |
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83 | |
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84 | for klass in (BytesIO, BufferedReader, BufferedWriter, BufferedRandom, |
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85 | BufferedRWPair): |
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86 | BufferedIOBase.register(klass) |
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87 | |
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88 | for klass in (StringIO, TextIOWrapper): |
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89 | TextIOBase.register(klass) |
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90 | del klass |
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