case FAMILY_OS2:
                return actualOsName.contains(FAMILY_OS2);
            case FAMILY_NETWARE:
                return actualOsName.contains(FAMILY_NETWARE);
            case FAMILY_DOS:
                return PATH_SEP.equals(";") && !isFamily(FAMILY_NETWARE, actualOsName) && !isWindows;
            case FAMILY_MAC:

      <configuration>
        <![CDATA[
    <offline>true</offline>
    ]]></configuration>
      <description>
        <![CDATA[
      Flags the system as offline, to prevent accessing the network to resolve artifacts or execute plugins.

      NOTE: It's also possible to switch to offline mode on a per-build basis, using the '-o' command-line option.
    ]]></description>
    </expression>
    <expression>

        if (metadata == null) {
            metadata = this.metadata;

            changed = true;
        } else {
            changed = metadata.merge(this.metadata);
        }

        // beware meta-versions!
        String version = metadata.getVersion();
        if (Artifact.LATEST_VERSION.equals(version) || Artifact.RELEASE_VERSION.equals(version)) {

    /**
     * Indicates whether network access to remote repositories has been disabled.
     *
     * @return {@code true} if remote access has been disabled, {@code false} otherwise.
     */
    boolean isOffline();

    /**
     * Enables/disables network access to remote repositories.
     *
     * @param offline {@code true} to disable remote access, {@code false} to allow network access.

            // ---------------------------------------------------------------------------------
            // I'm not sure if this last regexp was really intended to disallow the usage of
            // network paths as user.home directory. Unfortunately it did. I removed it and
            // have not detected any problems yet.
            // ---------------------------------------------------------------------------------

    /**
     * Indicates whether network access to remote repositories has been disabled.
     *
     * @return {@code true} if remote access has been disabled, {@code false} otherwise.
     */
    boolean isOffline();

    /**
     * Enables/disables network access to remote repositories.
     *
     * @param offline {@code true} to disable remote access, {@code false} to allow network access.