Hello,
There are three ways to apply directive in general that i know of, others 
may chose to implement it slightly differently.
1. Use directives supplied with networker install and apply them to each 
networker client 
2. Placing nsr file ( specifics are in admin guide) under the directory 
you want to apply them to
3. Creating the directive via networker user program and applying them. ( 
Details on it under user guide)
Depending on OS any number of methods and it's variants can be utilized, 
check admin guide starting page 149 ( V 7.3.2-Windows)
In your case try ( substitute /tmp with the directory of choice, this 
should skip everything under /tmp directory, if you want tmp directory 
show up in client index then you could add null to the directive .
<< /tmp >>
        skip: .?* *

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