github.com/vieux/docker@v0.6.3-0.20161004191708-e097c2a938c7/docs/reference/commandline/exec.md (about) 1 <!--[metadata]> 2 +++ 3 title = "exec" 4 description = "The exec command description and usage" 5 keywords = ["command, container, run, execute"] 6 [menu.main] 7 parent = "smn_cli" 8 +++ 9 <![end-metadata]--> 10 11 # exec 12 13 ```markdown 14 Usage: docker exec [OPTIONS] CONTAINER COMMAND [ARG...] 15 16 Run a command in a running container 17 18 Options: 19 -d, --detach Detached mode: run command in the background 20 --detach-keys Override the key sequence for detaching a container 21 --help Print usage 22 -i, --interactive Keep STDIN open even if not attached 23 --privileged Give extended privileges to the command 24 -t, --tty Allocate a pseudo-TTY 25 -u, --user Username or UID (format: <name|uid>[:<group|gid>]) 26 ``` 27 28 The `docker exec` command runs a new command in a running container. 29 30 The command started using `docker exec` only runs while the container's primary 31 process (`PID 1`) is running, and it is not restarted if the container is 32 restarted. 33 34 If the container is paused, then the `docker exec` command will fail with an error: 35 36 $ docker pause test 37 test 38 $ docker ps 39 CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 40 1ae3b36715d2 ubuntu:latest "bash" 17 seconds ago Up 16 seconds (Paused) test 41 $ docker exec test ls 42 FATA[0000] Error response from daemon: Container test is paused, unpause the container before exec 43 $ echo $? 44 1 45 46 ## Examples 47 48 $ docker run --name ubuntu_bash --rm -i -t ubuntu bash 49 50 This will create a container named `ubuntu_bash` and start a Bash session. 51 52 $ docker exec -d ubuntu_bash touch /tmp/execWorks 53 54 This will create a new file `/tmp/execWorks` inside the running container 55 `ubuntu_bash`, in the background. 56 57 $ docker exec -it ubuntu_bash bash 58 59 This will create a new Bash session in the container `ubuntu_bash`.