doc: lead with example, add missing links

Signed-off-by: Joachim Wiberg <[email protected]>

README.md

@@ -9,7 +9,6 @@ Table of Contents
 -----------------
 
 * [Introduction](#introduction)
-* [Usage](#usage)
 * [Features](doc/features.md)
   - [Delegating Reboot](doc/features.md#delegating-reboot)
   - [Built-in Monitors](doc/features.md#built-in-monitors)
@@ -163,7 +162,6 @@ the `watchdogd` project, copyright © [Ron Leishman][].
 [Coverity Scan]:     https://scan.coverity.com/projects/6458
 [Coverity Status]:   https://scan.coverity.com/projects/6458/badge.svg
 [GitHub]:            http://github.com/troglobit/watchdogd
-[ex1]:               https://github.com/troglobit/watchdogd/blob/master/examples/ex1.c
 [LICENSE]:           https://github.com/troglobit/watchdogd/blob/master/LICENSE
 [contrib]:           https://github.com/troglobit/watchdogd/blob/master/.github/CONTRIBUTING.md
 [Joachim Wiberg]:    http://troglobit.com

doc/advanced.md

@@ -15,7 +15,7 @@ debug log level, without having to restart a running daemon.
 
 
 <a href="https://codedocs.xyz/troglobit/watchdogd/wdog_8h.html"><img
-   align="right"  src="doc/api.png" alt="API" title="API docs"></a>
+   align="right"  src="api.png" alt="API" title="API docs"></a>
 
 libwdog API
 -----------
@@ -24,6 +24,41 @@ To have `watchdogd` supervise a process, it must be instrumented with at
 least a "subscribe" and a "kick" API call.  Commonly this is achieved by
 adding the `wdog_kick()` call to the main event loop.
 
+🕮 <https://codedocs.xyz/troglobit/watchdogd/wdog_8h.html>
+
+### Example
+
+For other applications, identify your main loop, its max period time and
+instrument it like this:
+
+```C
+int ack, wid;
+
+/* Library will use process' name on NULL first arg. */
+wid = wdog_subscribe(NULL, 10000, &ack);
+if (-1 == wid)
+        ;      /* Error handling */
+
+while (1) {
+        ...
+        /* Ensure kick is called periodically, < 10 sec */
+        wdog_kick2(wid, &ack);
+        ...
+}
+```
+
+This example subscribe to the watchdog with a 10 sec timeout.  The `wid`
+is used in the call to `wdog_kick2()`, with the received `ack` value.
+Which is changed every time the application calls `wdog_kick2()`, so it
+is important the correct value is used.  Applications should of course
+check the return value of `wdog_subscribe()` for errors, that code is
+left out for readability.
+
+See also the [example/ex1.c][ex1] in the source distribution.  This is
+used by the automatic tests.
+
+### API
+
 All libwdog API functions, except `wdog_ping()`, return POSIX OK(0) or
 negative value with `errno` set on error.  The `wdog_subscribe()` call
 returns a positive integer (including zero) for the watchdog `id`.
@@ -58,34 +93,5 @@ similar.  For such libraries one can simply add a timer callback for the
 kick to run periodically to monitor proper operation of the client.
 
 
-### Example
-
-For other applications, identify your main loop, its max period time and
-instrument it like this:
-
-```C
-int ack, wid;
-
-/* Library will use process' name on NULL first arg. */
-wid = wdog_subscribe(NULL, 10000, &ack);
-if (-1 == wid)
-        ;      /* Error handling */
-
-while (1) {
-        ...
-        /* Ensure kick is called periodically, < 10 sec */
-        wdog_kick2(wid, &ack);
-        ...
-}
-```
-
-This example subscribe to the watchdog with a 10 sec timeout.  The `wid`
-is used in the call to `wdog_kick2()`, with the received `ack` value.
-Which is changed every time the application calls `wdog_kick2()`, so it
-is important the correct value is used.  Applications should of course
-check the return value of `wdog_subscribe()` for errors, that code is
-left out for readability.
-
-See also the [example/ex1.c][ex1] in the source distribution.  This is
-used by the automatic tests.
-
+[libuEv]:  https://github.com/troglobit/libuev/
+[ex1]:     https://github.com/troglobit/watchdogd/blob/master/examples/ex1.c