github.com/brahmaroutu/docker@v1.2.1-0.20160809185609-eb28dde01f16/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    -d, --detach         Detached mode: run command in the background
    19    --detach-keys        Override the key sequence for detaching a container
    20    --help               Print usage
    21    -i, --interactive    Keep STDIN open even if not attached
    22    --privileged         Give extended privileges to the command
    23    -t, --tty            Allocate a pseudo-TTY
    24    -u, --user           Username or UID (format: <name|uid>[:<group|gid>])
    25  ```
    26  
    27  The `docker exec` command runs a new command in a running container.
    28  
    29  The command started using `docker exec` only runs while the container's primary
    30  process (`PID 1`) is running, and it is not restarted if the container is
    31  restarted.
    32  
    33  If the container is paused, then the `docker exec` command will fail with an error:
    34  
    35      $ docker pause test
    36      test
    37      $ docker ps
    38      CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS                   PORTS               NAMES
    39      1ae3b36715d2        ubuntu:latest       "bash"              17 seconds ago      Up 16 seconds (Paused)                       test
    40      $ docker exec test ls
    41      FATA[0000] Error response from daemon: Container test is paused, unpause the container before exec
    42      $ echo $?
    43      1
    44  
    45  ## Examples
    46  
    47      $ docker run --name ubuntu_bash --rm -i -t ubuntu bash
    48  
    49  This will create a container named `ubuntu_bash` and start a Bash session.
    50  
    51      $ docker exec -d ubuntu_bash touch /tmp/execWorks
    52  
    53  This will create a new file `/tmp/execWorks` inside the running container
    54  `ubuntu_bash`, in the background.
    55  
    56      $ docker exec -it ubuntu_bash bash
    57  
    58  This will create a new Bash session in the container `ubuntu_bash`.