libaio 0.4

Linux AIO API wrapper

Contents

• python 2 Notes

Linux AIO API wrapper

This is about in-kernel, file-descriptor-based asynchronous I/O. It has nothing to do with the asyncio standard module.

python 2 Notes

In python 2.7, a memoryview of a bytearray, despite being writable, is rejected by ctypes:

>>> from ctypes import c_char
>>> a = bytearray(b'foo')
>>> c_char.from_buffer(a)
c_char('f')
>>> b = memoryview(a)
>>> b.readonly
False
>>> c_char.from_buffer(b)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: expected a writeable buffer object

This means that it is not possible to only read or write a few bytes at the beginning of a large buffer without having to copy memory.

The same code works fine with python 3.x .

This is considered as python 2.7 ctypes bug, and not a python-libaio bug.