A simple plugin can always be configured entirely on the command line. But if you need to incorporate more complex defaults, or if parameters should not appear as arguments in the process list, a configuration file may be of use. The module
Nagios::Plugin enables you to access configuration files in a simple manner—one reason certainly being to encourage plugin programmers to use a uniform format, since this would considerably simplify configuration work for the Nagios admin, who no longer has to get used to different formats for every plugin.
Nagios::Plugin provides an interface for the module
Config::Tiny. The file format corresponds to that of the INI files:
rootproperty=10.0 [math] pi=3.1415 euler=2.78
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