_io._IOBase - pydoc - phpman

Help on class _IOBase in _io:

_io._IOBase = class _IOBase(builtins.object)
 |  The abstract base class for all I/O classes.
 |
 |  This class provides dummy implementations for many methods that
 |  derived classes can override selectively; the default implementations
 |  represent a file that cannot be read, written or seeked.
 |
 |  Even though IOBase does not declare read, readinto, or write because
 |  their signatures will vary, implementations and clients should
 |  consider those methods part of the interface. Also, implementations
 |  may raise UnsupportedOperation when operations they do not support are
 |  called.
 |
 |  The basic type used for binary data read from or written to a file is
 |  bytes. Other bytes-like objects are accepted as method arguments too.
 |  In some cases (such as readinto), a writable object is required. Text
 |  I/O classes work with str data.
 |
 |  Note that calling any method (except additional calls to close(),
 |  which are ignored) on a closed stream should raise a ValueError.
 |
 |  IOBase (and its subclasses) support the iterator protocol, meaning
 |  that an IOBase object can be iterated over yielding the lines in a
 |  stream.
 |
 |  IOBase also supports the :keyword:`with` statement. In this example,
 |  fp is closed after the suite of the with statement is complete:
 |
 |  with open('spam.txt', 'r') as fp:
 |      fp.write('Spam and eggs!')
 |
 |  Methods defined here:
 |
 |  __del__(...)
 |
 |  __enter__(...)
 |
 |  __exit__(...)
 |
 |  __iter__(self, /)
 |      Implement iter(self).
 |
 |  __next__(self, /)
 |      Implement next(self).
 |
 |  close(self, /)
 |      Flush and close the IO object.
 |
 |      This method has no effect if the file is already closed.
 |
 |  fileno(self, /)
 |      Returns underlying file descriptor if one exists.
 |
 |      OSError is raised if the IO object does not use a file descriptor.
 |
 |  flush(self, /)
 |      Flush write buffers, if applicable.
 |
 |      This is not implemented for read-only and non-blocking streams.
 |
 |  isatty(self, /)
 |      Return whether this is an 'interactive' stream.
 |
 |      Return False if it can't be determined.
 |
 |  readable(self, /)
 |      Return whether object was opened for reading.
 |
 |      If False, read() will raise OSError.
 |
 |  readline(self, size=-1, /)
 |      Read and return a line from the stream.
 |
 |      If size is specified, at most size bytes will be read.
 |
 |      The line terminator is always b'\n' for binary files; for text
 |      files, the newlines argument to open can be used to select the line
 |      terminator(s) recognized.
 |
 |  readlines(self, hint=-1, /)
 |      Return a list of lines from the stream.
 |
 |      hint can be specified to control the number of lines read: no more
 |      lines will be read if the total size (in bytes/characters) of all
 |      lines so far exceeds hint.
 |
 |  seek(...)
 |      Change stream position.
 |
 |      Change the stream position to the given byte offset. The offset is
 |      interpreted relative to the position indicated by whence.  Values
 |      for whence are:
 |
 |      * 0 -- start of stream (the default); offset should be zero or positive
 |      * 1 -- current stream position; offset may be negative
 |      * 2 -- end of stream; offset is usually negative
 |
 |      Return the new absolute position.
 |
 |  seekable(self, /)
 |      Return whether object supports random access.
 |
 |      If False, seek(), tell() and truncate() will raise OSError.
 |      This method may need to do a test seek().
 |
 |  tell(self, /)
 |      Return current stream position.
 |
 |  truncate(...)
 |      Truncate file to size bytes.
 |
 |      File pointer is left unchanged.  Size defaults to the current IO
 |      position as reported by tell().  Returns the new size.
 |
 |  writable(self, /)
 |      Return whether object was opened for writing.
 |
 |      If False, write() will raise OSError.
 |
 |  writelines(self, lines, /)
 |      Write a list of lines to stream.
 |
 |      Line separators are not added, so it is usual for each of the
 |      lines provided to have a line separator at the end.
 |
 |  ----------------------------------------------------------------------
 |  Static methods defined here:
 |
 |  __new__(*args, **kwargs) from builtins.type
 |      Create and return a new object.  See help(type) for accurate signature.
 |
 |  ----------------------------------------------------------------------
 |  Data descriptors defined here:
 |
 |  __dict__
 |
 |  closed