docker/cli · info · cancelledErr

container prune has been cancelled

Error message

container prune has been cancelled

What it means

Returned by runPrune wrapped in a cancelledErr (which implements Cancelled()) when the user answers 'no' to the interactive prune confirmation prompt. It is not a daemon failure; it signals the operation was intentionally aborted by the user. The prompt only appears when --force is not set.

Solutions

1. Re-run and confirm with 'y', or use `docker container prune -f` to skip the prompt.
2. In scripts, detect the Cancelled() error type and treat it as a no-op rather than a failure.
3. Ensure stdin is a TTY if you want the prompt to appear interactively.

Example fix

// before
docker container prune   # user typed 'n'

// after
docker container prune -f

// If non-interactive, default force=true to skip the prompt entirely.
if !interactive {
    options.force = true
}

// Detect a user cancellation by the Cancelled() marker interface.
func isCancelled(err error) bool {
    var c interface{ Cancelled() }
    return errors.As(err, &c)
}

_, _, err := runPrune(ctx, cli, options)
if err != nil {
    var c interface{ Cancelled() }
    if errors.As(err, &c) {
        // user declined — not a failure
        return nil
    }
    return err
}

When it happens

Trigger: Running `docker container prune` (without -f) and typing 'n' at the 'Are you sure you want to continue?' prompt, or piping 'n'/'no' into stdin. prompt.Confirm returns false and the function returns the cancelled error.

Common situations: Interactive scripts that auto-answer 'n'. CI wrappers echoing 'n' to avoid accidental deletion. Aborted cleanup during manual exploration.

Related errors

• builder prune has been cancelled
• containers prune has been cancelled
• cannot attach to a stopped container, start it first
• cannot attach to a paused container, unpause it first
• cannot attach to a restarting container, wait until it is…

AI-assisted analysis of docker/cli@4f84911bfe (2026-08-07). Data as JSON: /api/errors/ff4968474657e937. Report an issue: GitHub.

Appendix: source

Thrown at cli/command/container/prune.go:74

	flags.BoolVarP(&options.force, "force", "f", false, "Do not prompt for confirmation")
	flags.Var(&options.filter, "filter", `Provide filter values (e.g. "until=<timestamp>")`)

	return cmd
}

const warning = `WARNING! This will remove all stopped containers.
Are you sure you want to continue?`

func runPrune(ctx context.Context, dockerCli command.Cli, options pruneOptions) (spaceReclaimed uint64, output string, _ error) {
	pruneFilters := command.PruneFilters(dockerCli, options.filter.Value())

	if !options.force {
		r, err := prompt.Confirm(ctx, dockerCli.In(), dockerCli.Out(), warning)
		if err != nil {
			return 0, "", err
		}
		if !r {
			return 0, "", cancelledErr{errors.New("container prune has been cancelled")}
		}
	}

	res, err := dockerCli.Client().ContainerPrune(ctx, client.ContainerPruneOptions{
		Filters: pruneFilters,
	})
	if err != nil {
		return 0, "", err
	}

	var out strings.Builder
	if len(res.Report.ContainersDeleted) > 0 {
		out.WriteString("Deleted Containers:\n")
		for _, id := range res.Report.ContainersDeleted {
			out.WriteString(id + "\n")
		}
		spaceReclaimed = res.Report.SpaceReclaimed
	}

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