`docker run -v`: Copy all files from container to host?

General
1

I have the following command:
docker run -it -v ~/Desktop:/var/task mylambda bash

From my understanding, this command here will mount a volume so all files inside /var/task within my container will be copied to ~/Desktop. But that’s not the case. Do I misunderstand that command? How do I otherwise get /var/task/lambdatest.zip to my localhost?

2

the host is always the master, so files on your desktop will sync to the container.
is the file generated or is it there from the start?
because if you mount it this way, and the file will be created at some point, the file should be created.

Also you might need to try with an empty folder, and try and use the full path to the folder