ahmetb/kubectx · error

failed to reset file %d: %w

Error message

failed to reset file %d: %w

What it means

In the per-file Save loop, Reset() (truncate/reposition the backing file) failed for file i. Fires when the write handle cannot truncate: read-only file, permission changed since parse, or a non-regular backing file. No files have been re-encoded yet at this point in that iteration.

Source

Thrown at internal/kubeconfig/kubeconfig.go:206

			seen[n] = true
			elements = append(elements, rn)
		}
	}

	if len(elements) == 0 {
		return nil, nil
	}
	seqNode := &yaml.Node{Kind: yaml.SequenceNode, Tag: "!!seq"}
	for _, elem := range elements {
		seqNode.Content = append(seqNode.Content, elem.YNode())
	}
	return yaml.NewRNode(seqNode), nil
}

func (k *Kubeconfig) Save() error {
	for i := range k.files {
		if err := k.files[i].f.Reset(); err != nil {
			return fmt.Errorf("failed to reset file %d: %w", i, err)
		}
		enc := yaml.NewEncoder(k.files[i].f)
		enc.SetIndent(0)
		if err := enc.Encode(k.files[i].config.YNode()); err != nil {
			return fmt.Errorf("failed to encode file %d: %w", i, err)
		}
		if err := enc.Close(); err != nil {
			return fmt.Errorf("failed to close encoder for file %d: %w", i, err)
		}
	}
	return nil
}

View on GitHub (pinned to 12ad6fb22e)

Solutions

1. Check write permission on the N-th KUBECONFIG file
2. Remove read-only flags/immutable attributes
3. Ensure the file is a regular writable file, then retry the switch

When it happens

Trigger: Thrown at internal/kubeconfig/kubeconfig.go:206 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of ahmetb/kubectx@12ad6fb22e (2026-09-02). Data as JSON: /api/errors/b56b1bf66ed8c329. Report an issue: GitHub.