To way to tell Splunk to split configuration parameters into a list of parameters is via the introspection XML scheme. For example, on Windows, the perfmon input uses this feature:
b:\>%splunk_home%\etc\system\bin\perfmon.cmd --scheme
<scheme>
[...skipped...]
<arg name="counters">
<title>counters</title>
<list_delimiter>;</list_delimiter>
<required_on_create>false</required_on_create>
</arg>
The presence of "list_delimiter" tells Splunk that "counters" is a multi-value parameter, and that the delimiter is ";". This will cause the configuration setting to be split by that delimiter.
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