Does asyncio supports asynchronous I/O for file op

Question

Does asyncio supports asynchronous I/O for file operations? If yes, how I can use this in Python 3.5 with async/await syntax code?

Answer 1

That depends what library you use.

curio offers this functionality, https://curio.readthedocs.io/en/latest/reference.html#module-curio.file

plain asyncio doesn't, but there are 3rd party libraries, e.g. https://github.com/Tinche/aiofiles (which is really synchronous file access isolated in threads)

Modern operating systems do provide asynchronous file primitives, but these are varied, thus each would need own implementation. Please compare:

• http://man7.org/linux/man-pages/man7/aio.7.html
• https://msdn.microsoft.com/en-us/library/windows/desktop/aa365683(v=vs.85).aspx
• https://developer.apple.com/library/content/documentation/FileManagement/Conceptual/FileSystemProgrammingGuide/TechniquesforReadingandWritingCustomFiles/TechniquesforReadingandWritingCustomFiles.html

I suspect someone will soon rip out underlying async io from node.js and make a decent Python library, or perhaps someone already has.

Answer 2

asyncio does not have support for this. However, aiofiles supports just this. Please have a look.

Answer 3

Most operating systems don't support asynchronous file operations. That's why asyncio doesn't support them either.

See the asyncio wiki for further explanation.