command: docker exec
short: Run a command in a running container
long: |-
  The `docker exec` command runs a new command in a running container.

  The command started using `docker exec` only runs while the container's primary
  process (`PID 1`) is running, and it is not restarted if the container is
  restarted.

  COMMAND will run in the default directory of the container. If the
  underlying image has a custom directory specified with the WORKDIR directive
  in its Dockerfile, this will be used instead.

  COMMAND should be an executable, a chained or a quoted command
  will not work. Example: `docker exec -ti my_container "echo a && echo b"` will
  not work, but `docker exec -ti my_container sh -c "echo a && echo b"` will.
usage: docker exec [OPTIONS] CONTAINER COMMAND [ARG...]
pname: docker
plink: docker.yaml
options:
- option: detach
  shorthand: d
  value_type: bool
  default_value: "false"
  description: 'Detached mode: run command in the background'
  deprecated: false
  experimental: false
  experimentalcli: false
  kubernetes: false
  swarm: false
- option: detach-keys
  value_type: string
  description: Override the key sequence for detaching a container
  deprecated: false
  experimental: false
  experimentalcli: false
  kubernetes: false
  swarm: false
- option: env
  shorthand: e
  value_type: list
  description: Set environment variables
  deprecated: false
  min_api_version: "1.25"
  experimental: false
  experimentalcli: false
  kubernetes: false
  swarm: false
- option: interactive
  shorthand: i
  value_type: bool
  default_value: "false"
  description: Keep STDIN open even if not attached
  deprecated: false
  experimental: false
  experimentalcli: false
  kubernetes: false
  swarm: false
- option: privileged
  value_type: bool
  default_value: "false"
  description: Give extended privileges to the command
  deprecated: false
  experimental: false
  experimentalcli: false
  kubernetes: false
  swarm: false
- option: tty
  shorthand: t
  value_type: bool
  default_value: "false"
  description: Allocate a pseudo-TTY
  deprecated: false
  experimental: false
  experimentalcli: false
  kubernetes: false
  swarm: false
- option: user
  shorthand: u
  value_type: string
  description: 'Username or UID (format: <name|uid>[:<group|gid>])'
  deprecated: false
  experimental: false
  experimentalcli: false
  kubernetes: false
  swarm: false
- option: workdir
  shorthand: w
  value_type: string
  description: Working directory inside the container
  deprecated: false
  min_api_version: "1.35"
  experimental: false
  experimentalcli: false
  kubernetes: false
  swarm: false
examples: |-
  ### Run `docker exec` on a running container

  First, start a container.

  ```bash
  $ docker run --name ubuntu_bash --rm -i -t ubuntu bash
  ```

  This will create a container named `ubuntu_bash` and start a Bash session.

  Next, execute a command on the container.

  ```bash
  $ docker exec -d ubuntu_bash touch /tmp/execWorks
  ```

  This will create a new file `/tmp/execWorks` inside the running container
  `ubuntu_bash`, in the background.

  Next, execute an interactive `bash` shell on the container.

  ```bash
  $ docker exec -it ubuntu_bash bash
  ```

  This will create a new Bash session in the container `ubuntu_bash`.

  Next, set an environment variable in the current bash session.

  ```bash
  $ docker exec -it -e VAR=1 ubuntu_bash bash
  ```

  This will create a new Bash session in the container `ubuntu_bash` with environment
  variable `$VAR` set to "1". Note that this environment variable will only be valid
  on the current Bash session.

  By default `docker exec` command runs in the same working directory set when container was created.

  ```bash
  $ docker exec -it ubuntu_bash pwd
  /
  ```

  You can select working directory for the command to execute into

  ```bash
  $ docker exec -it -w /root ubuntu_bash pwd
  /root
  ```


  ### Try to run `docker exec` on a paused container

  If the container is paused, then the `docker exec` command will fail with an error:

  ```bash
  $ docker pause test

  test

  $ docker ps

  CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS                   PORTS               NAMES
  1ae3b36715d2        ubuntu:latest       "bash"              17 seconds ago      Up 16 seconds (Paused)                       test

  $ docker exec test ls

  FATA[0000] Error response from daemon: Container test is paused, unpause the container before exec

  $ echo $?
  1
  ```
deprecated: false
experimental: false
experimentalcli: false
kubernetes: false
swarm: false