his
example, transactions are necessary to ensure that either all or none
of the data items appear in case of system or application failure.</p>
      <pre class="programlisting">int
main(int argc, char *argv)
{
    extern int optind;
    DB *db_cats, *db_color, *db_fruit;
    DB_ENV *dbenv;
    int ch;

    while ((ch = getopt(argc, argv, "")) != EOF)
        switch (ch) {
        case '?':
        default:
            usage();
        }
    argc -= optind;
    argv += optind;

    env_dir_create();
    en