trivial changes to Perl plugin section.

git-svn-id: https://nagiosplug.svn.sourceforge.net/svnroot/nagiosplug/nagiosplug/trunk@924 f882894a-f735-0410-b71e-b25c423dba1c

diff --git a/doc/developer-guidelines.sgml b/doc/developer-guidelines.sgml
index 064bd9245e1770a8780798194de52c06598bb2a9..9ec3f94e808518fa68f42ad6eb9466f69ee029fa 100644 (file)
--- a/doc/developer-guidelines.sgml
+++ b/doc/developer-guidelines.sgml
@@ -407,12 +407,12 @@
                <orderedlist>
                        
                        <listitem><para> Do not use BEGIN and END blocks since they will be called 
-                       the first time and when Nagios shuts down with Embedded Perl (ePN).  In 
+                       only once (when Nagios starts and shuts down) with Embedded Perl (ePN).  In 
                        particular, do not use BEGIN blocks to initialize variables.</para>
                        </listitem>
          
                        <listitem><para>To use utils.pm, you need to provide a full path to the
-                       module in order for it to work with ePN.</para>
+                       module in order for it to work.</para>
                        
          <literallayout>
          e.g.
@@ -429,16 +429,18 @@
                        variable. </para>
                        
 
-                       <para>Explicitly initialize each varialable in use.  Otherwise with
-                       caching enabled, the plugin will not be recompilied each time, and
+                       <para>Explicitly initialize each variable in use.  Otherwise with
+                       caching enabled, the plugin will not be recompiled each time, and
                        therefore Perl will not reinitialize all the variables.  All old
                        variable values will still be in effect.</para>
                        </listitem>
                        
-                       <listitem><para>Do not use &gt; DATA &lt; (these simply do not compile under ePN).</para>
+                       <listitem><para>Do not use &gt;DATA&lt; handles (these simply do not compile under ePN).</para>
                        </listitem>
 
-                       <listitem><para>Do not use named subroutines</para> 
+                       <listitem><para>Do not use global variables in named subroutines. This is bad practise anyway, but with ePN the
+                       compiler will report an error "&lt;global_var&gt; will not stay shared ..". Values used by
+                       subroutines should be passed in the argument list.</para> 
                        </listitem>
 
                        <listitem><para>If writing to a file (perhaps recording
@@ -449,7 +451,10 @@
                
                        <listitem><para>As in <xref linkend="runtime"> all plugins need 
                        to monitor their runtime, specially if they are using network
-                       resources.  Use of the <emphasis>alarm</emphasis> is recommended.
+                       resources.  Use of the <emphasis>alarm</emphasis> is recommended
+                       noting that some Perl modules (eg LWP) manage timers, so that an alarm
+                       set by a plugin using such a module is overwritten by the module.
+                       (workarounds are cunning (TM) or using the module timer)
                        Plugins may import a default time out ($TIMEOUT) from utils.pm.
                        </para>
                        </listitem>