diff options
Diffstat (limited to 'doc/developer-guidelines.sgml')
| -rw-r--r-- | doc/developer-guidelines.sgml | 19 |
1 files changed, 12 insertions, 7 deletions
diff --git a/doc/developer-guidelines.sgml b/doc/developer-guidelines.sgml index 064bd924..9ec3f94e 100644 --- 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 > DATA < (these simply do not compile under ePN).</para> + <listitem><para>Do not use >DATA< 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 "<global_var> 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> |