mirror of https://github.com/docker/cli.git
111 lines
3.2 KiB
Markdown
111 lines
3.2 KiB
Markdown
---
|
|
title: "exec"
|
|
description: "The exec command description and usage"
|
|
keywords: "command, container, run, execute"
|
|
---
|
|
|
|
<!-- This file is maintained within the docker/docker Github
|
|
repository at https://github.com/docker/docker/. Make all
|
|
pull requests against that repo. If you see this file in
|
|
another repository, consider it read-only there, as it will
|
|
periodically be overwritten by the definitive file. Pull
|
|
requests which include edits to this file in other repositories
|
|
will be rejected.
|
|
-->
|
|
|
|
# exec
|
|
|
|
```markdown
|
|
Usage: docker exec [OPTIONS] CONTAINER COMMAND [ARG...]
|
|
|
|
Run a command in a running container
|
|
|
|
Options:
|
|
-d, --detach Detached mode: run command in the background
|
|
--detach-keys Override the key sequence for detaching a container
|
|
-e, --env=[] Set environment variables
|
|
--help Print usage
|
|
-i, --interactive Keep STDIN open even if not attached
|
|
--privileged Give extended privileges to the command
|
|
-t, --tty Allocate a pseudo-TTY
|
|
-u, --user Username or UID (format: <name|uid>[:<group|gid>])
|
|
```
|
|
|
|
## Description
|
|
|
|
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. It 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.
|
|
|
|
## 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.
|
|
|
|
|
|
### 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
|
|
```
|