Bug: unable to tail /var/log/nginx/access.log: tomb: still alive

[Enteee]

With version 0.7.0, when I try to tail nginx's /var/log/nginx/access.log to stdout using -stdout /var/log/nginx/access.log, instead of printing the access log, I get for each request a line:

 Warning: unable to tail /var/log/nginx/access.log: tomb: still alive

This repeats ~30 times until dockerize finally stops nginx and the container crashes.

Minimal reproducible example

• Dockerfile

ARG debian_version=10.13
FROM debian:${debian_version} AS build

MAINTAINER Ente "ducksource@duckpond.ch"

# Build dockerize
ARG dockerize_version=0.7.0
RUN set -ex \
  && apt-get update \
  && DEBIAN_FRONTEND=noninteractive \
    apt-get install --no-install-recommends --no-install-suggests -y \
      wget ca-certificates \
      inotify-tools \
  && wget \
    "https://github.com/jwilder/dockerize/releases/download/v${dockerize_version}/dockerize-linux-amd64-v${dockerize_version}.tar.gz" \
  && tar -C "/usr/local/bin" -xzvf "dockerize-linux-amd64-v${dockerize_version}.tar.gz" \
  && rm "dockerize-linux-amd64-v${dockerize_version}.tar.gz"

FROM debian:${debian_version}

# Install dockerize
RUN set -ex \
  && apt-get update \
  && DEBIAN_FRONTEND=noninteractive \
    apt-get install --no-install-recommends --no-install-suggests -y \
      inotify-tools
COPY --from=build  /usr/local/bin/dockerize /usr/local/bin/dockerize

1. Build container: docker build .
2. Run dockerize in container

$ docker run -ti <image_id> bash

root@32e1af5fc110:/service# touch stdout
root@32e1af5fc110:/service# dockerize -stdout stdout

3. Then in a new terminal:

$ docker exec -ti $(docker ps -q) bash
root@32e1af5fc110:/service# echo "AA" > stdout

4. Check output of first terminal:

root@32e1af5fc110:/service# dockerize -stdout stdout 
2023/06/11 08:39:29 Warning: unable to tail stdout: tomb: still alive

[munir131]

I am getting that error on version 0.6.1 too

[Enteee]

@munir131 are you sure? I can not reproduce this issue with version 0.6.1.
In my example I changed ARG dockerize_version=0.7.0 to ARG dockerize_version=0.6.1 and it worked just fine.

[munir131]

@Enteee My bad. We are not getting that issue on 0.6.1. It is only on 0.7.0

[kaisensan]

I'm also facing this issue on v0.9.2. Is anyone looking into it?

FWIW, the only workaround I could find was to stick with v0.6.1.

[kaisensan]

It seems 28ad938 introduced this error. I'm still trying to understand what it aimed to fix in the first place.

@sychan any help is appreciated!