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================================================================= sniffio: Sniff out which async library your code is running under

You're writing a library. You've decided to be ambitious, and support multiple async I/O packages, like Trio <https://trio.readthedocs.io>, and asyncio <https://docs.python.org/3/library/asyncio.html>, and ... You've written a bunch of clever code to handle all the differences. But... how do you know which piece of clever code to run?

This is a tiny package whose only purpose is to let you detect which async library your code is running under.

• Documentation: https://sniffio.readthedocs.io

• Bug tracker and source code: https://github.com/python-trio/sniffio

• License: MIT or Apache License 2.0, your choice

• Contributor guide: https://trio.readthedocs.io/en/latest/contributing.html

• Code of conduct: Contributors are requested to follow our code of conduct <https://trio.readthedocs.io/en/latest/code-of-conduct.html>_ in all project spaces.

This library is maintained by the Trio project, as a service to the async Python community as a whole.

Quickstart

.. code-block:: python3

from sniffio import current_async_library import trio import asyncio

async def print_library(): library = current_async_library() print("This is:", library)

Prints "This is trio"

trio.run(print_library)

Prints "This is asyncio"

asyncio.run(print_library())

For more details, including how to add support to new async libraries, please peruse our fine manual <https://sniffio.readthedocs.io>__.