docker change Ctrl+p to something else?

Docker has a configuration file and you can change the detach binding by adding

{
    "detachKeys": "ctrl-z,z"
}

to ~/.docker/config.json.

If there are other entries in config.json then just add the “detachKeys” entry as the last one. For example:

{
    "HttpHeaders": {
        "User-Agent": "Docker-Client/19.03.11 (linux)"
    },
    "detachKeys": "ctrl-z,z"
}

Note: If you are running docker using sudo docker ... the .docker directory with the configuration file must be in the root’s home directory (i.e., /root/.docker/config.json).