run_process fails when running from .exe console_script entrypoint on windows

[graingert]

Things to check first

• I have searched the existing issues and didn't find my bug already reported there

• I have checked that my bug is still present in the latest release

AnyIO version

4.3.0

Python version

3.11.3

What happened?

running:

import anyio.to_process

from fastapi import FastAPI


app = FastAPI()

def sync_example():
    return 1

@app.get("/")
async def example() -> int:
    return await anyio.to_process.run_sync(sync_example)

with uvicorn demo:app fails with:

Traceback (most recent call last):
  File "C:\Users\User\uvicron_demo\Lib\site-packages\anyio\to_process.py", line 163, in run_sync
    await send_raw_command(pickled)
  File "C:\Users\User\uvicron_demo\Lib\site-packages\anyio\to_process.py", line 89, in send_raw_command
    raise retval
FileNotFoundError: [Errno 2] No such file or directory: 'C:\\Users\\User\\uvicron_demo\\Scripts\\uvicorn.exe\\__main__.py'

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "C:\Users\User\uvicron_demo\Lib\site-packages\uvicorn\protocols\http\h11_impl.py", line 412, in run_asgi
    result = await app(  # type: ignore[func-returns-value]
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\User\uvicron_demo\Lib\site-packages\uvicorn\middleware\proxy_headers.py", line 84, in __call__
    return await self.app(scope, receive, send)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\User\uvicron_demo\Lib\site-packages\fastapi\applications.py", line 1054, in __call__
    await super().__call__(scope, receive, send)
  File "C:\Users\User\uvicron_demo\Lib\site-packages\starlette\applications.py", line 123, in __call__
    await self.middleware_stack(scope, receive, send)
  File "C:\Users\User\uvicron_demo\Lib\site-packages\starlette\middleware\errors.py", line 186, in __call__
    raise exc
  File "C:\Users\User\uvicron_demo\Lib\site-packages\starlette\middleware\errors.py", line 164, in __call__
    await self.app(scope, receive, _send)
  File "C:\Users\User\uvicron_demo\Lib\site-packages\starlette\middleware\exceptions.py", line 62, in __call__
    await wrap_app_handling_exceptions(self.app, conn)(scope, receive, send)
  File "C:\Users\User\uvicron_demo\Lib\site-packages\starlette\_exception_handler.py", line 64, in wrapped_app
    raise exc
  File "C:\Users\User\uvicron_demo\Lib\site-packages\starlette\_exception_handler.py", line 53, in wrapped_app
    await app(scope, receive, sender)
  File "C:\Users\User\uvicron_demo\Lib\site-packages\starlette\routing.py", line 758, in __call__
    await self.middleware_stack(scope, receive, send)
  File "C:\Users\User\uvicron_demo\Lib\site-packages\starlette\routing.py", line 778, in app
    await route.handle(scope, receive, send)
  File "C:\Users\User\uvicron_demo\Lib\site-packages\starlette\routing.py", line 299, in handle
    await self.app(scope, receive, send)
  File "C:\Users\User\uvicron_demo\Lib\site-packages\starlette\routing.py", line 79, in app
    await wrap_app_handling_exceptions(app, request)(scope, receive, send)
  File "C:\Users\User\uvicron_demo\Lib\site-packages\starlette\_exception_handler.py", line 64, in wrapped_app
    raise exc
  File "C:\Users\User\uvicron_demo\Lib\site-packages\starlette\_exception_handler.py", line 53, in wrapped_app
    await app(scope, receive, sender)
  File "C:\Users\User\uvicron_demo\Lib\site-packages\starlette\routing.py", line 74, in app
    response = await func(request)
               ^^^^^^^^^^^^^^^^^^^
  File "C:\Users\User\uvicron_demo\Lib\site-packages\fastapi\routing.py", line 278, in app
    raw_response = await run_endpoint_function(
                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\User\uvicron_demo\Lib\site-packages\fastapi\routing.py", line 191, in run_endpoint_function
    return await dependant.call(**values)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\User\demo.py", line 13, in example
    return await anyio.to_process.run_sync(sync_example)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\User\uvicron_demo\Lib\site-packages\anyio\to_process.py", line 168, in run_sync
    raise BrokenWorkerProcess(
anyio.BrokenWorkerProcess: Error during worker process initialization

How can we reproduce the bug?

see above

[agronholm]

Where should it get the interpreter path then?

[graingert]

sys.executable ?