Included a section explaining the basics of the code

diff --git a/Readme b/Readme
index 72000fb..17add93 100644 (file)
--- a/Readme
+++ b/Readme
@@ -1,3 +1,13 @@
+     Table of Contents
+=======================================
+1. Introduction
+2. Code Conventions
+3. Source Code
+4. Configuration File
+5. References
+
+
+
 1.   Introduction
 =======================================
 This application provides means to check the availability of remote hosts
@@ -17,16 +27,18 @@ The host's address can be an IP or a DNS.
 There are many ways to invoke the application, the simplest is just type:
   ./libpingcheck
 which uses the configuration values from the configuration file (describled in
-section 4.Configuration file).
+the Configuration File section).
 
 
 1.3. Resources
 ---------------------------------------
-Further information about the problem domain can be found in the following
-resources:
-- http://tools.ietf.org/html/rfc792
-- http://en.wikipedia.org/wiki/Ping
-- http://en.wikipedia.org/wiki/Internet_Control_Message_Protocol
+Further information about the problem domain can be found in the References
+section.
+
+
+1.4. Legal Issues
+---------------------------------------
+All rights reserved to Intra2net AG.
 
 
 
@@ -91,8 +103,46 @@ The sources are spread over these distincts directories:
 - conf: keeps default and example configuration files.
 
 
+3.2. Main concept of application operation
+---------------------------------------
+This application makes extensive use of asynchronous timers-handlers from
+Boost ASIO. So this section describes briefly how ASIO works. More information
+can be found in the References section.
+
+The basic idea is to have a handler which will be called when a timer expires.
+After the timer expires, you have to schedule the timer again to call your
+handler once more. Given the declaration of the timer:
+
+    boost::asio::deadline_timer my_timer( my_io_service );
+
+you must specify when it will expire:
+
+    my_timer.expires_at( some_time_in_seconds + seconds( interval_in_seconds ) );
+
+and which method will handle when the timer expires.
+
+    my_timer.async_wait( boost::bind( &MyClass::my_handle_method, this ) );
+
+Then, the my_io_service service can be called to perform a loop:
+
+    my_io_service.run();
+
+
 
 4.   Configuration file
 =======================================
+In this section are describled the configuration items, along with they
+possible values and meanings.
+- limit-to-notify: range from 0 to the number of hosts available. This value
+  represents minimum number of hosts that have to fail (i.e. do not reply the
+  ping) in order to alert any external system.
 
 
+
+5.   References
+=======================================
+[1]  http://tools.ietf.org/html/rfc792
+[2]  http://en.wikipedia.org/wiki/Ping
+[3]  http://en.wikipedia.org/wiki/Internet_Control_Message_Protocol
+[4]  http://www.boost.org/doc/libs/1_45_0/doc/html/boost_asio.html
+[5]  http://www.boost.org/doc/libs/1_45_0/doc/html/program_options.html