Setting REMOVE_VOLUMES=1 causes docker-gc to exit with status 1

[makkes]

Description

When setting REMOVE_VOLUMES=1 and there are no volumes found in Docker then docker-gc exits with status code 1 because of grep returning 1 when it has not found any matches.

How to reproduce

1. Make sure that no Docker volumes exist on the system
2. Run REMOVE_VOLUMES=1 docker-gc

What do you expect

docker-gc should exit with status code 0.

What happened instead

docker-gc exits with status code 1.

Software:

• bash version: Any

Full backtrace

$ docker volume ls
DRIVER              VOLUME NAME
$ sudo REMOVE_VOLUMES=1 ./docker-gc
$ echo $?
1

[makkes]

The main problem we have with this currently is that we call docker-gc from a systemd unit and systemd then marks the unit as failed.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[makkes]

@mattnworb @davidxia There's an open PR to fix this issue (#202) that is waiting to be merged. Would you be able to merge the PR or provide feedback, please?

[davidxia]

Sorry for the delay. I just merged it.