chenhg5/cc-connect · error

backup old binary: %w

Error message

backup old binary: %w

What it means

Wraps a failed os.Rename moving the current executable aside to <target>.old in replaceExecutable (the Windows-safe swap path). It fires when the running binary cannot be renamed — target missing, permission denied, or antivirus locking the file on Windows.

Source

Thrown at cmd/cc-connect/update.go:439

	}
	tmp.Close()

	fmt.Printf("Downloaded %.1f MB\n", float64(size)/1024/1024)
	return tmp.Name(), nil
}

func replaceExecutable(target, src string) error {
	if err := os.Chmod(src, 0o755); err != nil {
		return fmt.Errorf("chmod: %w", err)
	}

	// On Windows, rename over a running exe is not possible directly.
	// Move old binary aside, then move new one in.
	backup := target + ".old"
	os.Remove(backup)

	if err := os.Rename(target, backup); err != nil {
		return fmt.Errorf("backup old binary: %w", err)
	}

	if err := copyFile(src, target); err != nil {
		// Attempt to restore
		if restoreErr := os.Rename(backup, target); restoreErr != nil {
			slog.Warn("update: failed to restore old binary after copy error", "error", restoreErr)
		}
		return fmt.Errorf("install new binary: %w", err)
	}

	if err := os.Chmod(target, 0o755); err != nil {
		return fmt.Errorf("chmod new binary: %w", err)
	}

	os.Remove(backup)
	return nil
}

View on GitHub (pinned to 4000b2338a)

Solutions

1. On Windows, exclude the cc-connect directory from antivirus locking
2. Ensure the install directory is writable by the updating user
3. Retry once the lock is released

When it happens

Trigger: Thrown at cmd/cc-connect/update.go:439 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of chenhg5/cc-connect@4000b2338a (2026-09-06). Data as JSON: /api/errors/ff762472a3fccfef. Report an issue: GitHub.