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| <h3 class="section">28.1 NSS Basics</h3> |
| |
| <p>The basic idea is to put the implementation of the different services |
| offered to access the databases in separate modules. This has some |
| advantages: |
| |
| <ol type=1 start=1> |
| <li>Contributors can add new services without adding them to GNU C Library. |
| <li>The modules can be updated separately. |
| <li>The C library image is smaller. |
| </ol> |
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| <p>To fulfill the first goal above the ABI of the modules will be described |
| below. For getting the implementation of a new service right it is |
| important to understand how the functions in the modules get called. |
| They are in no way designed to be used by the programmer directly. |
| Instead the programmer should only use the documented and standardized |
| functions to access the databases. |
| |
| <p class="noindent">The databases available in the NSS are |
| |
| <p><a name="index-ethers-3252"></a><a name="index-group-3253"></a><a name="index-hosts-3254"></a><a name="index-netgroup-3255"></a><a name="index-networks-3256"></a><a name="index-protocols-3257"></a><a name="index-passwd-3258"></a><a name="index-rpc-3259"></a><a name="index-services-3260"></a><a name="index-shadow-3261"></a> |
| <dl> |
| <dt><code>aliases</code><a name="index-aliases-3262"></a><dd>Mail aliases |
| <!-- @pxref{Mail Aliases}. --> |
| <br><dt><code>ethers</code><a name="index-ethers-3263"></a><dd>Ethernet numbers, |
| <!-- @pxref{Ethernet Numbers}. --> |
| <br><dt><code>group</code><a name="index-group-3264"></a><dd>Groups of users, see <a href="Group-Database.html#Group-Database">Group Database</a>. |
| <br><dt><code>hosts</code><a name="index-hosts-3265"></a><dd>Host names and numbers, see <a href="Host-Names.html#Host-Names">Host Names</a>. |
| <br><dt><code>netgroup</code><a name="index-netgroup-3266"></a><dd>Network wide list of host and users, see <a href="Netgroup-Database.html#Netgroup-Database">Netgroup Database</a>. |
| <br><dt><code>networks</code><a name="index-networks-3267"></a><dd>Network names and numbers, see <a href="Networks-Database.html#Networks-Database">Networks Database</a>. |
| <br><dt><code>protocols</code><a name="index-protocols-3268"></a><dd>Network protocols, see <a href="Protocols-Database.html#Protocols-Database">Protocols Database</a>. |
| <br><dt><code>passwd</code><a name="index-passwd-3269"></a><dd>User passwords, see <a href="User-Database.html#User-Database">User Database</a>. |
| <br><dt><code>rpc</code><a name="index-rpc-3270"></a><dd>Remote procedure call names and numbers, |
| <!-- @pxref{RPC Database}. --> |
| <br><dt><code>services</code><a name="index-services-3271"></a><dd>Network services, see <a href="Services-Database.html#Services-Database">Services Database</a>. |
| <br><dt><code>shadow</code><a name="index-shadow-3272"></a><dd>Shadow user passwords, |
| <!-- @pxref{Shadow Password Database}. --> |
| </dl> |
| |
| <p class="noindent">There will be some more added later (<code>automount</code>, <code>bootparams</code>, |
| <code>netmasks</code>, and <code>publickey</code>). |
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