comparison build/README.linux @ 239:cc467e52da4c

* Add platform README files

+
+The Vamp Plugin SDK -- Platform Notes for Linux and other GNU platforms
+=======================================================================
+
+Building at the command line
+----------------------------
+
+To build the SDK, example plugins, and command-line host, first edit
+the Makefile to suit your platform according to the comments in it,
+then run "make".
+
+Note that you must have libsndfile
+(http://www.mega-nerd.com/libsndfile/) installed in order to build the
+command-line host successfully.  To build only the SDK and examples,
+run "make sdk examples" instead of just "make".
+
+
+Installing the Example Plugins
+------------------------------
+
+To install the example plugins so you can load them in Vamp hosts,
+copy the files
+
+   examples/vamp-example-plugins.so
+and
+   examples/vamp-example-plugins.cat
+
+to
+   /usr/local/lib/vamp/
+or 
+   $HOME/vamp/
+
+
+Plugin Linkage
+--------------
+
+Vamp plugins are distributed as dynamic libraries (.so files).  A
+properly packaged Vamp plugin library should export exactly one public
+symbol, namely the Vamp API entry point vampGetPluginDescriptor.
+
+The default for the GNU linker is to export all of the symbols in the
+library.  This will work (the host will be able to load the plugin),
+but it unnecessarily pollutes the host's symbol namespace, it may
+cause symbol collisions in some esoteric circumstances, and it
+increases the amount of time the plugin takes to load.
+
+To improve this behaviour, you can instruct the linker to export only
+the one required symbol using a linker script.  To do this, place the
+text
+
+{
+	global: vampGetPluginDescriptor;
+	local: *;
+};
+
+into a text file, and then use the --version-script option to the
+linker to tell it to refer to this file.  All other symbols will then
+be properly hidden.
+
+The Makefile included in this SDK uses this method to manage symbol
+visibility for the included example plugins, using the file
+build/vamp-plugin.map.  There are other methods that will work too,
+but this one is simple and has the advantage of requiring no changes
+to the code.
+