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doc/manual.md

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+libspnav manual
+===============
+
+Table of contents
+-----------------
+- [About libspnav](#about-libspnav)
+- [Quick start](#quick-start)
+- [Native libspnav API](#native-libspnav-api)
+   - [Initialization and cleanup](#initialization-and-cleanup)
+   - [Input events](#input-events)
+   - [Device information](#device-information)
+   - [Configuration management](#configuration-management)
+- [Magellan API](#magellan-api)
+
+About libspnav
+--------------
+Libspnav is a C library which can be used to communicate, and receive
+6dof input events, from the free spacenav driver, or the proprietary
+3dconnexion driver.
+
+There are two modes of operation supported by libspnav. It can
+communicate through a custom spacenav protocol, which works over UNIX
+domain sockets, or it can communicate through the X11 magellan protocol
+based on `ClientMessage` events. The first mode of operation is
+only compatible with spacenavd, but provides extended functionality, and
+does not need an X server to be running to function.  The second mode can
+be used to talk to either spacenavd or the 3Dconnexion 3dxsrv driver, but
+only supports a very limited subset of features, and depends on X11.
+
+To be continued ...
+