How to enable persistent data from within the container

[Marietto2008]

Hello.

let's say that I want to upgrade all the packages inside the container and I want that the changes sticks forever when I run again the container. how can I do that ?

[carlosperate]

You can mount your own image into the docker container and any changes will be persistent inside that image:
https://github.com/lukechilds/dockerpi#usage

[Marietto2008]

I'm not sure that it is what I want to do. U mean that I can use my own image. But this presumes that I should prepare in advance my own image and when the docker container will be used,it will use only the informations already saved inside the image,without adding new informations WHILE I'm using the container. I mean,I want to use the container in realtime and at some point,I want to save the informations that are inside of it and when I will close docker,the next time that I will open it again,I will find the updated informations. It's not a good idea to do like you suggest,because it needs another method to add the informations inside the IMG file. why using another method,if docker can do everything ?