Docker : error when delete running containers

Question

I am trying to remove running containers and delete all downloaded images by using below commands:

docker ps -aq | xargs docker rm -f

docker images -aq | xargs docker rmi -f

But I got this

"docker rm" requires at least 1 argument.
See 'docker rm --help'.

Usage:  docker rm [OPTIONS] CONTAINER [CONTAINER...]

and

"docker rmi" requires at least 1 argument.
See 'docker rmi --help'.

Usage:  docker rmi [OPTIONS] IMAGE [IMAGE...]

this is my environment

Client:
 Version:      17.09.0-ce
 API version:  1.32
 Go version:   go1.8.3
 Git commit:   afdb6d4
 Built:        Tue Sep 26 22:42:18 2017
 OS/Arch:      linux/amd64

Server:
 Version:      17.09.0-ce
 API version:  1.32 (minimum version 1.12)
 Go version:   go1.8.3
 Git commit:   afdb6d4
 Built:        Tue Sep 26 22:40:56 2017
 OS/Arch:      linux/amd64
 Experimental: false
docker-compose version 1.16.1, build 6d1ac21
docker-py version: 2.5.1
CPython version: 2.7.13
OpenSSL version: OpenSSL 1.0.1t  3 May 2016

Is something wrong here? please help! Thanks

Answer 1

Use -r with xargs, it means not to execute if empty:

docker ps -aq | xargs -r docker rm -f
docker images -aq | xargs -r docker rmi -f

Answer 2

You need to first stop running container then remove them

docker stop $(docker ps -a -q)
docker rm $(docker ps -a -q)

For images try to remove dangling images

docker rmi $(docker images -f dangling=true -q)

To remove all images use

docker rmi $(docker images -q)