docker
Docker build is not recognising the `-e` flag for the echo command
Description
I'm not sure how to categorise this but it seems like unexpected behaviour. I'm running a simple command such as echo -e "BEGINNING OF FILE\n\n" > .tmpfile
When I run this from the docker image it outputs as expected. When I run this within a 'RUN' command in the Dockerfile it outputs the '-e' flag as part of the output e.g. "-e BEGINNING OF FILE".
I have no idea why it's outputting the -e flag directly.
Reproduce
Add this step to the Docker file:
RUN echo -e "BEGINNING OF FILE\n\n" > .tmpfile
Expected behavior
The output should be:
BEGINNING OF FILE
But is actually:
-e BEGINNING OF FILE
docker version
Client: Docker Engine - Community
Version: 25.0.3
API version: 1.44
Go version: go1.21.6
Git commit: 4debf41
Built: Tue Feb 6 21:13:09 2024
OS/Arch: linux/amd64
Context: default
Server: Docker Engine - Community
Engine:
Version: 25.0.3
API version: 1.44 (minimum version 1.24)
Go version: go1.21.6
Git commit: f417435
Built: Tue Feb 6 21:13:09 2024
OS/Arch: linux/amd64
Experimental: false
containerd:
Version: 1.6.28
GitCommit: ae07eda36dd25f8a1b98dfbf587313b99c0190bb
runc:
Version: 1.1.12
GitCommit: v1.1.12-0-g51d5e94
docker-init:
Version: 0.19.0
GitCommit: de40ad0
docker info
Client: Docker Engine - Community
Version: 25.0.3
Context: default
Debug Mode: false
Plugins:
buildx: Docker Buildx (Docker Inc.)
Version: v0.12.1
Path: /usr/libexec/docker/cli-plugins/docker-buildx
compose: Docker Compose (Docker Inc.)
Version: v2.24.6
Path: /usr/libexec/docker/cli-plugins/docker-compose
scout: Docker Scout (Docker Inc.)
Version: v1.0.8
Path: /home/andrew/.docker/cli-plugins/docker-scout
Server:
Containers: 4
Running: 4
Paused: 0
Stopped: 0
Images: 11
Server Version: 25.0.3
Storage Driver: overlay2
Backing Filesystem: extfs
Supports d_type: true
Using metacopy: false
Native Overlay Diff: true
userxattr: false
Logging Driver: json-file
Cgroup Driver: systemd
Cgroup Version: 2
Plugins:
Volume: local
Network: bridge host ipvlan macvlan null overlay
Log: awslogs fluentd gcplogs gelf journald json-file local splunk syslog
Swarm: inactive
Runtimes: io.containerd.runc.v2 runc
Default Runtime: runc
Init Binary: docker-init
containerd version: ae07eda36dd25f8a1b98dfbf587313b99c0190bb
runc version: v1.1.12-0-g51d5e94
init version: de40ad0
Security Options:
apparmor
seccomp
Profile: builtin
cgroupns
Kernel Version: 6.2.0-39-generic
Operating System: Ubuntu 23.04
OSType: linux
Architecture: x86_64
CPUs: 16
Total Memory: 62.52GiB
Name: kalpaitch-spinach
ID: a160b708-c811-46e9-9c47-389514f4b548
Docker Root Dir: /var/lib/docker
Debug Mode: false
Experimental: false
Insecure Registries:
127.0.0.0/8
Live Restore Enabled: false
Additional Info
No response
I'm not able to reproduce this issue using alpine as base-image;
docker build -t foo -<<'EOF'
FROM alpine
RUN echo -e "BEGINNING OF FILE\n\n" > .tmpfile
EOF
Build runs successfully;
[+] Building 1.5s (7/7) FINISHED docker:desktop-linux
=> [internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 96B 0.0s
=> [internal] load metadata for docker.io/library/alpine:latest 0.0s
=> [internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [1/2] FROM docker.io/library/alpine:latest@sha256:c5b1261d6d3e43071626931fc004f70149baeba2c8ec672bd4f27761f8e1ad6b 1.2s
=> => resolve docker.io/library/alpine:latest@sha256:c5b1261d6d3e43071626931fc004f70149baeba2c8ec672bd4f27761f8e1ad6b 1.2s
=> [auth] library/alpine:pull token for registry-1.docker.io 0.0s
=> [2/2] RUN echo -e "BEGINNING OF FILE\n\n" > .tmpfile 0.1s
=> exporting to image 0.1s
=> => exporting layers 0.0s
=> => exporting manifest sha256:07e9b08ca1e01a821c0779ed887a2ad47622da64c8bd558c757ada84bfdb97ab 0.0s
=> => exporting config sha256:e8769b3ba4c8f5e05d3c2b38644985cc74fb123b221a79fd99635b7663815811 0.0s
=> => exporting attestation manifest sha256:c93bcc769d1be9eca9549c10fe9828a49f922e8abc2c7423cbf6a5ff719b8c99 0.0s
=> => exporting manifest list sha256:97cab80709c4b973b084d9066f472d9dd242a395646bc6f9dfcfc0099b4f0fd3 0.0s
=> => naming to docker.io/library/foo:latest 0.0s
=> => unpacking to docker.io/library/foo:latest 0.0s
And checking the file shows the expected content;
docker run --rm foo cat /.tmpfile
BEGINNING OF FILE
However, the RUN command itself is executed in a container, so it depends on what base-image you're using; my example used alpine, but perhaps it doesn't work with other images; what image are you using as base-image?
I just came across this, too, using Ubuntu 22.04 base image. The build is run in a standard sh shell. When echo is invoked from sh it will have the -e behaviour by default.
So, at least for my case, I just omitted the -e and got the results I expected.
