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    if (r->header_only) {
        return OK;
    }

    /*
     * Now send our actual output.  Since we tagged this as being
     * "text/html", we need to embed any HTML.
     */
    ap_rputs(DOCTYPE_HTML_3_2, r);
    ap_rputs("<HTML>\n", r);
    ap_rputs(" <HEAD>\n", r);
    ap_rputs("  <TITLE>mod_example_hooks Module Content-Handler Output\n", r);
    ap_rputs("  </TITLE>\n", r);
    ap_rputs(" </HEAD>\n", r);
    ap_rputs(" <BODY>\n", r);
    ap_rputs("  <H1><SAMP>mod_example_hooks</SAMP> Module Content-Handler Output\n", r);
    ap_rputs("  </H1>\n", r);
    ap_rputs("  <P>\n", r);
    ap_rprintf(r, "  Apache HTTP Server version: \"%s\"\n",
            ap_get_server_banner());
    ap_rputs("  <BR>\n", r);
    ap_rprintf(r, "  Server built: \"%s\"\n", ap_get_server_built());
    ap_rputs("  </P>\n", r);
    ap_rputs("  <P>\n", r);
    ap_rputs("  The format for the callback trace is:\n", r);
    ap_rputs("  </P>\n", r);
    ap_rputs("  <DL>\n", r);
    ap_rputs("   <DT><EM>n</EM>.<SAMP>&lt;routine-name&gt;", r);
    ap_rputs("(&lt;routine-data&gt;)</SAMP>\n", r);
    ap_rputs("   </DT>\n", r);
    ap_rputs("   <DD><SAMP>[&lt;applies-to&gt;]</SAMP>\n", r);
    ap_rputs("   </DD>\n", r);
    ap_rputs("  </DL>\n", r);
    ap_rputs("  <P>\n", r);
    ap_rputs("  The <SAMP>&lt;routine-data&gt;</SAMP> is supplied by\n", r);
    ap_rputs("  the routine when it requests the trace,\n", r);
    ap_rputs("  and the <SAMP>&lt;applies-to&gt;</SAMP> is extracted\n", r);
    ap_rputs("  from the configuration record at the time of the trace.\n", r);
    ap_rputs("  <STRONG>SVR()</STRONG> indicates a server environment\n", r);
    ap_rputs("  (blank means the main or default server, otherwise it's\n", r);
    ap_rputs("  the name of the VirtualHost); <STRONG>DIR()</STRONG>\n", r);
    ap_rputs("  indicates a location in the URL or filesystem\n", r);
    ap_rputs("  namespace.\n", r);
    ap_rputs("  </P>\n", r);
    ap_rprintf(r, "  <H2>Startup callbacks so far:</H2>\n  <OL>\n%s  </OL>\n",
            trace);
    ap_rputs("  <H2>Connection-specific callbacks so far:</H2>\n", r);

    status =  apr_pool_userdata_get(&conn_data, CONN_NOTE,
                                    r->connection->pool);
    if ((status == APR_SUCCESS) && conn_data) {
        ap_rprintf(r, "  <OL>\n%s  </OL>\n", (char *) conn_data);
    }
    else {
        ap_rputs("  <P>No connection-specific callback information was "
                 "retrieved.</P>\n", r);
    }

    ap_rputs("  <H2>Request-specific callbacks so far:</H2>\n", r);
    ap_rprintf(r, "  <OL>\n%s  </OL>\n", apr_table_get(r->notes, TRACE_NOTE));
    ap_rputs("  <H2>Environment for <EM>this</EM> call:</H2>\n", r);
    ap_rputs("  <UL>\n", r);
    ap_rprintf(r, "   <LI>Applies-to: <SAMP>%s</SAMP>\n   </LI>\n", dcfg->loc);
    ap_rprintf(r, "   <LI>\"Example\" directive declared here: %s\n   </LI>\n",
            (dcfg->local ? "YES" : "NO"));
    ap_rprintf(r, "   <LI>\"Example\" inherited: %s\n   </LI>\n",
            (dcfg->congenital ? "YES" : "NO"));
    ap_rputs("  </UL>\n", r);
    ap_rputs(" </BODY>\n", r);
    ap_rputs("</HTML>\n", r);
    /*
     * We're all done, so cancel the timeout we set.  Since this is probably
     * the end of the request we *could* assume this would be done during
     * post-processing - but it's possible that another handler might be
     * called and inherit our outstanding timer.  Not good; to each its own.
     */
    /*
     * We did what we wanted to do, so tell the rest of the server we
     * succeeded.
     */
    return OK;
}

/*
 * The quick_handler hook presents modules with a very powerful opportunity to
 * serve their content in a very early request phase.  Note that this handler
 * can not serve any requests from the file system because hooks like
 * map_to_storage have not run.  The quick_handler hook also runs before any
 * authentication and access control.
 *
 * This hook is used by mod_cache to serve cached content.
 *
 * This is a RUN_FIRST hook. Return OK if you have served the request,
 * DECLINED if you want processing to continue, or a HTTP_* error code to stop
 * processing the request.
 */
static int x_quick_handler(request_rec *r, int lookup_uri)
{
    /*
     * Log the call and exit.
     */
    trace_request(r, "x_quick_handler()");
    return DECLINED;
}

/*
 * This routine is called just after the server accepts the connection,
 * but before it is handed off to a protocol module to be served.  The point
 * of this hook is to allow modules an opportunity to modify the connection
 * as soon as possible. The core server uses this phase to setup the
 * connection record based on the type of connection that is being used.
 *
 * This is a RUN_ALL hook.
 */
static int x_pre_connection(conn_rec *c, void *csd)
{
    char *note;

    /*
     * Log the call and exit.
     */
    note = apr_psprintf(c->pool, "x_pre_connection(c = %pp, p = %pp)",
                        (void*) c, (void*) c->pool);
    trace_connection(c, note);

    return OK;
}

/* This routine is used to actually process the connection that was received.
 * Only protocol modules should implement this hook, as it gives them an
 * opportunity to replace the standard HTTP processing with processing for
 * some other protocol.  Both echo and POP3 modules are available as
 * examples.
 *
 * This is a RUN_FIRST hook.
 */
static int x_process_connection(conn_rec *c)
{
    trace_connection(c, "x_process_connection()");
    return DECLINED;
}

/*
 * This routine is called after the request has been read but before any other
 * phases have been processed.  This allows us to make decisions based upon
 * the input header fields.
 *
 * This is a HOOK_VOID hook.
 */
static void x_pre_read_request(request_rec *r, conn_rec *c)
{
    /*
     * We don't actually *do* anything here, except note the fact that we were
     * called.
     */
    trace_request(r, "x_pre_read_request()");
}

/*
 * This routine is called after the request has been read but before any other
 * phases have been processed.  This allows us to make decisions based upon
 * the input header fields.
 *
 * This is a RUN_ALL hook.
 */
static int x_post_read_request(request_rec *r)
{
    /*
     * We don't actually *do* anything here, except note the fact that we were
     * called.
     */
    trace_request(r, "x_post_read_request()");
    return DECLINED;
}

/*
 * This routine gives our module an opportunity to translate the URI into an
 * actual filename.  If we don't do anything special, the server's default
 * rules (Alias directives and the like) will continue to be followed.
 *
 * This is a RUN_FIRST hook.
 */
static int x_translate_name(request_rec *r)
{
    /*
     * We don't actually *do* anything here, except note the fact that we were
     * called.
     */
    trace_request(r, "x_translate_name()");
    return DECLINED;
}

/*
 * This routine maps r->filename to a physical file on disk.  Useful for
 * overriding default core behavior, including skipping mapping for
 * requests that are not file based.
 *
 * This is a RUN_FIRST hook.
 */
static int x_map_to_storage(request_rec *r)
{
    /*
     * We don't actually *do* anything here, except note the fact that we were
     * called.
     */
    trace_request(r, "x_map_to_storage()");
    return DECLINED;
}

/*
 * this routine gives our module another chance to examine the request
 * headers and to take special action. This is the first phase whose
 * hooks' configuration directives can appear inside the <Directory>
 * and similar sections, because at this stage the URI has been mapped
 * to the filename. For example this phase can be used to block evil
 * clients, while little resources were wasted on these.
 *
 * This is a RUN_ALL hook.
 */
static int x_header_parser(request_rec *r)
{
    /*
     * We don't actually *do* anything here, except note the fact that we were
     * called.
     */
    trace_request(r, "x_header_parser()");
    return DECLINED;
}


/*
 * This routine is called to check for any module-specific restrictions placed
 * upon the requested resource.  (See the mod_access_compat module for an
 * example.)
 *
 * This is a RUN_ALL hook. The first handler to return a status other than OK
 * or DECLINED (for instance, HTTP_FORBIDDEN) aborts the callback chain.
 */
static int x_check_access(request_rec *r)
{
    trace_request(r, "x_check_access()");
    return DECLINED;
}

/*
 * This routine is called to check the authentication information sent with
 * the request (such as looking up the user in a database and verifying that
 * the [encrypted] password sent matches the one in the database).
 *
 * This is a RUN_FIRST hook. The return value is OK, DECLINED, or some
 * HTTP_mumble error (typically HTTP_UNAUTHORIZED).
 */
static int x_check_authn(request_rec *r)
{
    /*
     * Don't do anything except log the call.
     */
    trace_request(r, "x_check_authn()");
    return DECLINED;
}

/*
 * This routine is called to check to see if the resource being requested
 * requires authorisation.
 *
 * This is a RUN_FIRST hook. The return value is OK, DECLINED, or
 * HTTP_mumble.  If we return OK, no other modules are called during this
 * phase.
 *
 * If *all* modules return DECLINED, the request is aborted with a server
 * error.
 */
static int x_check_authz(request_rec *r)
{
    /*
     * Log the call and return OK, or access will be denied (even though we
     * didn't actually do anything).
     */
    trace_request(r, "x_check_authz()");
    return DECLINED;
}

/*
 * This routine is called to determine and/or set the various document type
 * information bits, like Content-type (via r->content_type), language, et
 * cetera.
 *
 * This is a RUN_FIRST hook.
 */
static int x_type_checker(request_rec *r)
{
    /*
     * Log the call, but don't do anything else - and report truthfully that
     * we didn't do anything.
     */
    trace_request(r, "x_type_checker()");
    return DECLINED;
}

/*
 * This routine is called to perform any module-specific fixing of header
 * fields, et cetera.  It is invoked just before any content-handler.
 *
 * This is a RUN_ALL HOOK.
 */
static int x_fixups(request_rec *r)
{
    /*
     * Log the call and exit.
     */
    trace_request(r, "x_fixups()");
    return DECLINED;
}

/*
 * This routine is called to perform any module-specific logging activities
 * over and above the normal server things.
 *
 * This is a RUN_ALL hook.
 */
static int x_log_transaction(request_rec *r)
{
    trace_request(r, "x_log_transaction()");
    return DECLINED;
}

#ifdef HAVE_UNIX_SUEXEC

/*
 * This routine is called to find out under which user id to run suexec
 * Unless our module runs CGI programs, there is no reason for us to
 * mess with this information.
 *
 * This is a RUN_FIRST hook. The return value is a pointer to an
 * ap_unix_identity_t or NULL.
 */
static ap_unix_identity_t *x_get_suexec_identity(const request_rec *r)
{
    trace_request(r, "x_get_suexec_identity()");
    return NULL;
}
#endif

/*
 * This routine is called to create a connection. This hook is implemented
 * by the Apache core: there is no known reason a module should override
 * it.
 *
 * This is a RUN_FIRST hook.
 *
 * Return NULL to decline, a valid conn_rec pointer to accept.
 */
static conn_rec *x_create_connection(apr_pool_t *p, server_rec *server,
                                     apr_socket_t *csd, long conn_id,
                                     void *sbh, apr_bucket_alloc_t *alloc)
{
    trace_nocontext(p, __FILE__, __LINE__, "x_create_connection()");
    return NULL;
}

/*
 * This hook is defined in server/core.c, but it is not actually called
 * or documented.
 *
 * This is a RUN_ALL hook.
 */
static int x_get_mgmt_items(apr_pool_t *p, const char *val, apr_hash_t *ht)
{
    /* We have nothing to do here but trace the call, and no context
     * in which to trace it.
     */
    trace_nocontext(p, __FILE__, __LINE__, "x_check_config()");
    return DECLINED;
}

/*
 * This routine gets called shortly after the request_rec structure
 * is created. It provides the opportunity to manipulae the request
 * at a very early stage.
 *
 * This is a RUN_ALL hook.
 */
static int x_create_request(request_rec *r)
{
    /*
     * We have a request_rec, but it is not filled in enough to give
     * us a usable configuration. So, add a trace without context.
     */
    trace_nocontext( r->pool, __FILE__, __LINE__, "x_create_request()");
    return DECLINED;
}

/*
 * This routine gets called during the startup of the MPM.
 * No known existing module implements this hook.
 *
 * This is a RUN_ALL hook.
 */
static int x_pre_mpm(apr_pool_t *p, ap_scoreboard_e sb_type)
{
    trace_nocontext(p, __FILE__, __LINE__, "x_pre_mpm()");
    return DECLINED;
}

/*
 * This hook gets run periodically by a maintenance function inside
 * the MPM. Its exact purpose is unknown and undocumented at this time.
 *
 * This is a RUN_ALL hook.
 */
static int x_monitor(apr_pool_t *p, server_rec *s)
{
    trace_nocontext(p, __FILE__, __LINE__, "x_monitor()");
    return DECLINED;
}

/*--------------------------------------------------------------------------*/
/*                                                                          */
/* Which functions are responsible for which hooks in the server.           */
/*                                                                          */
/*--------------------------------------------------------------------------*/
/*
 * Each function our module provides to handle a particular hook is
 * specified here.  The functions are registered using
 * ap_hook_foo(name, predecessors, successors, position)
 * where foo is the name of the hook.
 *
 * The args are as follows:
 * name         -> the name of the function to call.
 * predecessors -> a list of modules whose calls to this hook must be
 *                 invoked before this module.
 * successors   -> a list of modules whose calls to this hook must be
 *                 invoked after this module.
 * position     -> The relative position of this module.  One of
 *                 APR_HOOK_FIRST, APR_HOOK_MIDDLE, or APR_HOOK_LAST.
 *                 Most modules will use APR_HOOK_MIDDLE.  If multiple
 *                 modules use the same relative position, Apache will
 *                 determine which to call first.
 *                 If your module relies on another module to run first,
 *                 or another module running after yours, use the
 *                 predecessors and/or successors.
 *
 * The number in brackets indicates the order in which the routine is called
 * during request processing.  Note that not all routines are necessarily
 * called (such as if a resource doesn't have access restrictions).
 * The actual delivery of content to the browser [9] is not handled by
 * a hook; see the handler declarations below.
 */
static void x_register_hooks(apr_pool_t *p)
{
    ap_hook_pre_config(x_pre_config, NULL, NULL, APR_HOOK_MIDDLE);
    ap_hook_check_config(x_check_config, NULL, NULL, APR_HOOK_MIDDLE);
    ap_hook_test_config(x_test_config, NULL, NULL, APR_HOOK_MIDDLE);
    ap_hook_open_logs(x_open_logs, NULL, NULL, APR_HOOK_MIDDLE);
    ap_hook_post_config(x_post_config, NULL, NULL, APR_HOOK_MIDDLE);
    ap_hook_child_init(x_child_init, NULL, NULL, APR_HOOK_MIDDLE);
    ap_hook_handler(x_handler, NULL, NULL, APR_HOOK_MIDDLE);
    ap_hook_quick_handler(x_quick_handler, NULL, NULL, APR_HOOK_MIDDLE);
    ap_hook_pre_connection(x_pre_connection, NULL, NULL, APR_HOOK_MIDDLE);
    ap_hook_process_connection(x_process_connection, NULL, NULL, APR_HOOK_MIDDLE);
    ap_hook_pre_read_request(x_pre_read_request, NULL, NULL,
                              APR_HOOK_MIDDLE);
    /* [1] post read_request handling */
    ap_hook_post_read_request(x_post_read_request, NULL, NULL,
                              APR_HOOK_MIDDLE);
    ap_hook_log_transaction(x_log_transaction, NULL, NULL, APR_HOOK_MIDDLE);
    ap_hook_http_scheme(x_http_scheme, NULL, NULL, APR_HOOK_MIDDLE);
    ap_hook_default_port(x_default_port, NULL, NULL, APR_HOOK_MIDDLE);
    ap_hook_translate_name(x_translate_name, NULL, NULL, APR_HOOK_MIDDLE);
    ap_hook_map_to_storage(x_map_to_storage, NULL,NULL, APR_HOOK_MIDDLE);
    ap_hook_header_parser(x_header_parser, NULL, NULL, APR_HOOK_MIDDLE);
    ap_hook_fixups(x_fixups, NULL, NULL, APR_HOOK_MIDDLE);
    ap_hook_type_checker(x_type_checker, NULL, NULL, APR_HOOK_MIDDLE);
    ap_hook_check_access(x_check_access, NULL, NULL, APR_HOOK_MIDDLE,
                         AP_AUTH_INTERNAL_PER_CONF);
    ap_hook_check_authn(x_check_authn, NULL, NULL, APR_HOOK_MIDDLE,
                        AP_AUTH_INTERNAL_PER_CONF);
    ap_hook_check_authz(x_check_authz, NULL, NULL, APR_HOOK_MIDDLE,
                        AP_AUTH_INTERNAL_PER_CONF);
    ap_hook_insert_filter(x_insert_filter, NULL, NULL, APR_HOOK_MIDDLE);
    ap_hook_insert_error_filter(x_insert_error_filter, NULL, NULL, APR_HOOK_MIDDLE);
#ifdef HAVE_UNIX_SUEXEC
    ap_hook_get_suexec_identity(x_get_suexec_identity, NULL, NULL, APR_HOOK_MIDDLE);
#endif
    ap_hook_create_connection(x_create_connection, NULL, NULL, APR_HOOK_MIDDLE);
    ap_hook_get_mgmt_items(x_get_mgmt_items, NULL, NULL, APR_HOOK_MIDDLE);
    ap_hook_create_request(x_create_request, NULL, NULL, APR_HOOK_MIDDLE);
    ap_hook_pre_mpm(x_pre_mpm, NULL, NULL, APR_HOOK_MIDDLE);
    ap_hook_monitor(x_monitor, NULL, NULL, APR_HOOK_MIDDLE);
}

/*--------------------------------------------------------------------------*/
/*                                                                          */
/* All of the routines have been declared now.  Here's the list of          */
/* directives specific to our module, and information about where they      */
/* may appear and how the command parser should pass them to us for         */
/* processing.  Note that care must be taken to ensure that there are NO    */
/* collisions of directive names between modules.                           */
/*                                                                          */
/*--------------------------------------------------------------------------*/
/*
 * List of directives specific to our module.
 */
static const command_rec x_cmds[] =
{
    AP_INIT_NO_ARGS(
        "Example",                          /* directive name */
        cmd_example,                        /* config action routine */
        NULL,                               /* argument to include in call */
        OR_OPTIONS,                         /* where available */
        "Example directive - no arguments"  /* directive description */
    ),
    {NULL}
};
/*--------------------------------------------------------------------------*/
/*                                                                          */
/* Finally, the list of callback routines and data structures that provide  */
/* the static hooks into our module from the other parts of the server.     */
/*                                                                          */
/*--------------------------------------------------------------------------*/
/*
 * Module definition for configuration.  If a particular callback is not
 * needed, replace its routine name below with the word NULL.
 */
AP_DECLARE_MODULE(example_hooks) =
{
    STANDARD20_MODULE_STUFF,
    x_create_dir_config,    /* per-directory config creator */
    x_merge_dir_config,     /* dir config merger */
    x_create_server_config, /* server config creator */
    x_merge_server_config,  /* server config merger */
    x_cmds,                 /* command table */
    x_register_hooks,       /* set up other request processing hooks */
};
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