c-level stdout redirection on windows

redirect_to_devnull.py

# Redirect stdout at every level to /dev/null
import os
import io
import sys
import ctypes
from contextlib import contextmanager

@contextmanager
def stdout_redirector(stream):
    original_stdout_fd = sys.stdout.fileno()
    saved_stdout_fd = os.dup(original_stdout_fd)

    def _redirect_stdout(to_fd):
        """Redirect stdout to the given file descriptor."""
        # Flush the C-level buffer stdout
        ctypes.CDLL('api-ms-win-crt-stdio-l1-1-0').fflush(None)
        # Flush and close sys.stdout - also closes the file descriptor (fd)
        sys.stdout.close()
        # Make original_stdout_fd point to to_fd
        os.dup2(to_fd, original_stdout_fd)
        # Create a new sys.stdout that points to the redirected (original) fd
        sys.stdout = io.TextIOWrapper(os.fdopen(original_stdout_fd, 'wb'))

    try:
        devnull = open(os.devnull, 'w')
        _redirect_stdout(devnull.fileno())
        yield
        _redirect_stdout(saved_stdout_fd)
    except:
        os.close(saved_stdout_fd)

print('About to redirect to devnull...')

with stdout_redirector(io.BytesIO()):
    print('Python print statement')
    ctypes.CDLL('api-ms-win-crt-stdio-l1-1-0').puts(b'Some noisy C function')
    os.system('echo Even system echoes')

print('See? It ate everything. :)')