added section on tapsets

diff --git a/doc/SystemTap_Beginners_Guide/en-US/Understanding_How_SystemTap_Works.xml b/doc/SystemTap_Beginners_Guide/en-US/Understanding_How_SystemTap_Works.xml
index 76296507a5ac8be45e6fd9151b04b6db43bfe011..116e7453362f15757a4be8ddffa4196318ecdb6b 100644 (file)
--- a/doc/SystemTap_Beginners_Guide/en-US/Understanding_How_SystemTap_Works.xml
+++ b/doc/SystemTap_Beginners_Guide/en-US/Understanding_How_SystemTap_Works.xml
@@ -59,7 +59,34 @@
                
                <remark>
                        definition, significance, difference with stap scripts (previous section), library of tapsets in system: location
-               </remark>       
+               </remark>
+               
+               <para>
+                       <firstterm>Tapsets</firstterm> are scripts that form a library of pre-written probes and functions to be used in SystemTap scripts. When a user runs a SystemTap script, SystemTap checks the script's probe events and handlers against the tapset library; SystemTap then loads the corresponding probes and functions before translating the script to C (refer to <xref linkend="understanding-architecture-tools"/> for information on what transpires in a SystemTap session).
+               </para>
+<!--           
+               <para>
+                       Simply put, the tapset library is an abstraction layer designed to make it easier for users to define events and functions. In a way, tapsets provide useful "aliases" for functions that users may want to specify as an event; knowing the proper alias to use is, for the most part, easier than understanding how to specify a specific kernel function.
+               </para> 
+               -->
+               <para>
+                       Like SystemTap scripts, tapsets use the filename extension <filename>.stp</filename>. The standard library of tapsets is located in <filename>/usr/share/systemtap/tapset/</filename> by default. However, unlike SystemTap scripts, tapsets are not meant for direct execution; rather, they constitute the library from which other scripts can pull definitions.
+               </para> 
+               
+               
+               <para>
+                       Simply put, the tapset library is an abstraction layer designed to make it easier for users to define events and functions. In a manner of speaking, tapsets provide useful "aliases" for functions that users may want to specify as an event; knowing the proper alias to use is, for the most part, easier than understanding how to specify a specific kernel function.
+               </para> 
+                               
+               <para>
+                       Several handlers and functions in <xref linkend="systemtapscript-events"/> and <xref linkend="systemtapscript-handlers"/> are defined in tapsets. For example, <command>thread_indent()</command> is defined in <filename>indent.stp</filename>.
+               </para>
+               
+               
+<remark>
+       any other details to be included? i dont want to dwell too long here, though, since IMHO tapset development is beyond the scope of this "beginner's guide"
+</remark>      
+               
        </section>
 
 </chapter>