methods to incrementalcodecs.

Also forward port r54786 (fix the incremental
utf_8_sig decoder).

I'll add this step to PEP 306.

Don't read more than one line when reading text from a tty device.
Add peek() and read1() methods.
Return str instead of unicode when return ASCII characters in text mode.

Support ord(b) where b is a 1-byte string.
In zipfile.py, work around bytes being ints instead of chars, sometimes.

buffer-supporting objects (Unicode always excluded), and also of
str and bytes.
(For some reason u"" + b"" doesn't fail, I'll investigate later.)

Fix the truncate() semantics -- it should not affect the current position.
Switch wave.py/chunk.py to struct.unpack_from() to support bytes.
Don't use writelines() on binary files (test_fileinput.py).

not the number of array elements.

- 25% speed increse in tell();
- f.seek(0, 1) now maps to f.seek(f.tell(), 0) instead of to f.tell().

call self.buffer.tell().

Restore complex pickling.
Use cPickle in io.py.

without touching io.py or test_io.py.  The cause of the failure was that
bytes objects didn't pickle right.  As a stop-gap measure, I'm providing
bytes pickling via copy_reg.  Eventually, we should use a more efficient
protocol, e.g. __reduce_ex__ or __getstate__/__setstate__.

There is somewhat working (but slow) code supporting seek/tell for text files,
but extensive testing exposes a bug I can't nail down.

write() returns the number of bytes/characters written/buffered.
FileIO.close() calls self.flush().
Implement readinto() for buffered readers.
Tests th check all these.
Test proper behavior of __enter__/__exit__.

Reduce large file size to 2**31 (and a bit).

Etc., etc.

Removed unused _PyFileIO class.
Changed inheritance structure.
TODO: do the same kinds of things to TextIO.

Add tests for str <cmpop> bytes.

bytes objects can now be compared to anything that supports the buffer API.

(The new I/O library revealed the problem.)

Add closed attribute.
Support int argument to open() -- wrapping a file descriptor.
For b/w compat, support readline(n).
Support readlines() and readlines(n).
Flush on __del__.
Added some XXX comments.

instead of a filename.
Add a 'closed' attribute.

"import exceptions" to behave bizarrely.

(Should be backported to 2.6, really.)

This now appears to work when io.open is substituted for the real open
in fileinput.py -- at least the latter's unit tests pass.

Some cleanup of test_io.py and io.py.
Added seeking to buffered reader and writer, but no tests yet.