getzola/zola · error

Error setting Ctrl-C handler

Error message

Error setting Ctrl-C handler

What it means

serve() registers a ctrlc handler that cleans the site output folder when the user presses Ctrl+C, then calls .expect(...). The expect fires when the ctrlc crate fails to install the signal handler — typically because the OS disallows it for this process (restricted sandbox/container without SIGINT registration rights) or the platform is unsupported. Without the handler, Ctrl+C will terminate the process but skip the output-folder cleanup.

Source

Thrown at src/cmd/serve.rs:696

    log::info!(
        "Listening for changes in {}{}{{{}}}",
        root_dir.display(),
        MAIN_SEPARATOR,
        watch_list
    );

    let preserve_dotfiles_in_output = site.config.preserve_dotfiles_in_output;

    log::info!("Press Ctrl+C to stop\n");
    // Clean the output folder on ctrl+C
    ctrlc::set_handler(move || {
        match clean_site_output_folder(&output_path, preserve_dotfiles_in_output) {
            Ok(()) => (),
            Err(e) => log::error!("Errored while cleaning output folder: {e}"),
        }
        ::std::process::exit(0);
    })
    .expect("Error setting Ctrl-C handler");

    let reload_sass = |site: &Site, paths: &Vec<&PathBuf>| {
        let combined_paths =
            paths.iter().map(|p| p.display().to_string()).collect::<Vec<String>>().join(", ");
        log::info!("Sass file(s) changed {combined_paths}");
        rebuild_done_handling(
            &broadcaster,
            compile_sass(&site.base_path, &site.output_path),
            &site.sass_path.to_string_lossy(),
        );
    };

    let reload_templates = |site: &mut Site| {
        rebuild_done_handling(
            &broadcaster,
            site.reload_templates(),
            &site.templates_path.to_string_lossy(),
        );

View on GitHub (pinned to 61d3082821)

Solutions

1. Run the server outside sandboxes/containers that block signal handler registration
2. Degrade gracefully: log a warning and continue serving even if cleanup-on-exit cannot be installed
3. Clean the output folder on next startup instead of relying on exit-time cleanup

When it happens

Trigger: Thrown at src/cmd/serve.rs:696 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of getzola/zola@61d3082821 (2026-09-03). Data as JSON: /api/errors/989eb12c9eaf48ee. Report an issue: GitHub.