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<h3 class="section">28.4 Extending NSS</h3>

<p>One of the advantages of NSS mentioned above is that it can be extended
quite easily.  There are two ways in which the extension can happen:
adding another database or adding another service.  The former is
normally done only by the C library developers.  It is
here only important to remember that adding another database is
independent from adding another service because a service need not
support all databases or lookup functions.

   <p>A designer/implementor of a new service is therefore free to choose the
databases s/he is interested in and leave the rest for later (or
completely aside).

<ul class="menu">
<li><a accesskey="1" href="Adding-another-Service-to-NSS.html#Adding-another-Service-to-NSS">Adding another Service to NSS</a>:   What is to do to add a new service. 
<li><a accesskey="2" href="NSS-Module-Function-Internals.html#NSS-Module-Function-Internals">NSS Module Function Internals</a>:   Guidelines for writing new NSS
                                        service functions. 
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