- 1 year ago
Redirect multiprocessing.Process output properly
When using multiprocessing.Process
in Python, you can redirect the output of the subprocess by utilizing the stdout
and stderr
parameters of the Process
constructor. Here's an example of how you can redirect the output:
pythonimport multiprocessing
import sys
def worker_func():
# Print some output
print("Hello from worker process")
sys.stdout.flush()
if __name__ == "__main__":
# Create a pipe to redirect the output
parent_conn, child_conn = multiprocessing.Pipe()
# Create the worker process with output redirection
worker_process = multiprocessing.Process(target=worker_func, stdout=child_conn)
# Start the worker process
worker_process.start()
# Read the output from the child process
output = parent_conn.recv()
print("Output from worker process:", output)
# Wait for the worker process to finish
worker_process.join()
In this example, we use a multiprocessing.Pipe
to establish a communication channel between the parent process and the child process. The stdout
parameter of Process
is set to the child's end of the pipe (child_conn
) to redirect the output.
Inside the worker function (worker_func
in this case), we print some output. The sys.stdout.flush()
call ensures that the output is flushed and sent through the pipe immediately.
Back in the main process, we use parent_conn.recv()
to receive the output from the child process. This will block until there is something to read from the pipe. Finally, we print the received output.
Remember to join the worker process to wait for it to finish (worker_process.join()
).
With this approach, the output generated by the child process is redirected and read by the parent process, allowing you to handle it as needed.