annotate build/README.linux @ 253:683f4bc92a69

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author cannam
date Wed, 12 Nov 2008 09:44:24 +0000
parents cc467e52da4c
children 2e16d99867bd
rev   line source
cannam@239 1
cannam@239 2 The Vamp Plugin SDK -- Platform Notes for Linux and other GNU platforms
cannam@239 3 =======================================================================
cannam@239 4
cannam@239 5 Building at the command line
cannam@239 6 ----------------------------
cannam@239 7
cannam@253 8 To build the SDK, example plugins, and command-line host:
cannam@239 9
cannam@253 10 $ ./configure
cannam@253 11 $ make
cannam@253 12
cannam@253 13 To install after a successful make, run "make install" as root (or via
cannam@253 14 sudo).
cannam@239 15
cannam@239 16
cannam@239 17 Installing the Example Plugins
cannam@239 18 ------------------------------
cannam@239 19
cannam@239 20 To install the example plugins so you can load them in Vamp hosts,
cannam@239 21 copy the files
cannam@239 22
cannam@239 23 examples/vamp-example-plugins.so
cannam@239 24 and
cannam@239 25 examples/vamp-example-plugins.cat
cannam@239 26
cannam@239 27 to
cannam@239 28 /usr/local/lib/vamp/
cannam@239 29 or
cannam@239 30 $HOME/vamp/
cannam@239 31
cannam@239 32
cannam@239 33 Plugin Linkage
cannam@239 34 --------------
cannam@239 35
cannam@239 36 Vamp plugins are distributed as dynamic libraries (.so files). A
cannam@239 37 properly packaged Vamp plugin library should export exactly one public
cannam@239 38 symbol, namely the Vamp API entry point vampGetPluginDescriptor.
cannam@239 39
cannam@239 40 The default for the GNU linker is to export all of the symbols in the
cannam@239 41 library. This will work (the host will be able to load the plugin),
cannam@239 42 but it unnecessarily pollutes the host's symbol namespace, it may
cannam@239 43 cause symbol collisions in some esoteric circumstances, and it
cannam@239 44 increases the amount of time the plugin takes to load.
cannam@239 45
cannam@239 46 To improve this behaviour, you can instruct the linker to export only
cannam@239 47 the one required symbol using a linker script. To do this, place the
cannam@239 48 text
cannam@239 49
cannam@239 50 {
cannam@239 51 global: vampGetPluginDescriptor;
cannam@239 52 local: *;
cannam@239 53 };
cannam@239 54
cannam@239 55 into a text file, and then use the --version-script option to the
cannam@239 56 linker to tell it to refer to this file. All other symbols will then
cannam@239 57 be properly hidden.
cannam@239 58
cannam@239 59 The Makefile included in this SDK uses this method to manage symbol
cannam@239 60 visibility for the included example plugins, using the file
cannam@239 61 build/vamp-plugin.map. There are other methods that will work too,
cannam@239 62 but this one is simple and has the advantage of requiring no changes
cannam@239 63 to the code.
cannam@239 64