Bash

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Bash is the GNU Project’s Bourne Again SHell

GitHub repo: https://github.com/tianon/docker-bash

Library reference

This content is imported from the official Docker Library docs, and is provided by the original uploader. You can view the Docker Store page for this repo at https://store.docker.com/images/bash.

Supported tags and respective Dockerfile links

For detailed information about the published artifacts of each of the above supported tags (image metadata, transfer size, etc), please see the repos/bash directory in the docker-library/repo-info GitHub repo.

For more information about this image and its history, please see the relevant manifest file (library/bash). This image is updated via pull requests to the docker-library/official-images GitHub repo.

What is Bash?

Bash is the GNU Project’s Bourne Again SHell, a complete implementation of the IEEE POSIX and Open Group shell specification with interactive command line editing, job control on architectures that support it, csh-like features such as history substitution and brace expansion, and a slew of other features.

tiswww.case.edu/php/chet/bash/bashtop.html

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How to use this image

The primary use cases this image is targeting are testing new features of more recent Bash versions before your primary distribution updates packages and testing shell scripts against different Bash versions to ensure compatibility. There are likely other interesting use cases as well, but those are the primary two the image was initially created to solve!

Notes

There are a few main things that are important to note regarding this image:

  1. Bash itself is installed at /usr/local/bin/bash, not /bin/bash, so the recommended shebang is #!/usr/bin/env bash, not #!/bin/bash (or explicitly running your script via bash /.../script.sh instead of letting the shebang invoke Bash automatically). The image does not include /bin/bash, but if it is installed via the package manager included in the image, that package will install to /bin/bash and might cause confusion (although /usr/local/bin is ahead of /bin in $PATH, so as long as plain bash or /usr/bin/env are used consistently, the image-provided Bash will be preferred).

  2. Bash is the only thing included, so if your scripts rely on external tools (such as jq, for example), those will need to be added manually (via apk add --no-cache jq, for example).

Interactive shell

$ docker run -it --rm bash:4.4
bash-4.4# which bash
/usr/local/bin/bash
bash-4.4# echo $BASH_VERSION
4.4.0(1)-release

Testing scripts via bind-mount

$ docker run -it --rm -v /path/to/script.sh:/script.sh:ro bash:4.4 bash /script.sh
...
$ docker run -it --rm -v /path/to/script.sh:/script.sh:ro bash:3.2 bash /script.sh
...

Testing scripts via Dockerfile

FROM bash:4.4

COPY script.sh /

CMD ["bash", "/script.sh"]

Then, build and run the Docker image:

$ docker build -t my-bash-app .
...
$ docker run -it --rm --name my-running-app my-bash-app
...

License

Bash is free software, distributed under the terms of the GNU General Public License, version 3.

Supported Docker versions

This image is officially supported on Docker version 17.04.0-ce.

Support for older versions (down to 1.6) is provided on a best-effort basis.

Please see the Docker installation documentation for details on how to upgrade your Docker daemon.

User Feedback

Issues

If you have any problems with or questions about this image, please contact us through a GitHub issue. If the issue is related to a CVE, please check for a cve-tracker issue on the official-images repository first.

You can also reach many of the official image maintainers via the #docker-library IRC channel on Freenode.

Contributing

You are invited to contribute new features, fixes, or updates, large or small; we are always thrilled to receive pull requests, and do our best to process them as fast as we can.

Before you start to code, we recommend discussing your plans through a GitHub issue, especially for more ambitious contributions. This gives other contributors a chance to point you in the right direction, give you feedback on your design, and help you find out if someone else is working on the same thing.

Documentation

Documentation for this image is stored in the bash/ directory of the docker-library/docs GitHub repo. Be sure to familiarize yourself with the repository’s README.md file before attempting a pull request.

library, sample, Bash