_xnForceShutdown openni symbol not found - openni

Question

I had been trying to get OpenNI work on my Mac OS X 10.7. I installed the latest unstable binaries of OpenNI, NITE and Sensor from openni.org. The (precompiled) sample examples from OpenNI work fine but as soon as I write something of my own, it starts to fail.
For example, see below:
Undefined symbols for architecture x86_64:
"_xnForceShutdown", referenced from:
xn::Context::SetHandle(XnContext*) in sample.o
"_xnContextUnregisterFromShutdown", referenced from:
xn::Context::SetHandle(XnContext*) in sample.o
"_xnContextRelease", referenced from:
xn::Context::SetHandle(XnContext*) in sample.o
"_xnContextAddRef", referenced from:
xn::Context::SetHandle(XnContext*) in sample.o
"_xnContextRegisterForShutdown", referenced from:
xn::Context::SetHandle(XnContext*) in sample.o
ld: symbol(s) not found for architecture x86_64
collect2: ld returned 1 exit status
make: * [AsusCamera] Error 1
My code is as follows:
#include "XnOpenNI.h"
#include "XnCppWrapper.h"
using namespace xn;
extern "C" int printf(const char *, ...);
int main() {
Context context;
printf("hello world\n");
context.Release();
return 1;
};
Please help me. I already tried re-installing the libs several times.

Answer 1

I've just compiled your code on OSX (albeit 10.6.8) using Qt Creator and Xcode and it works.
The undefined symbols usually means you haven't linked to the library(dylib) the header files reference, so link libOpenNI.dylib to your project.
In Qt Creator I have this setup:
QT += core
QT -= gui
TARGET = niTest
CONFIG += console
CONFIG -= app_bundle
TEMPLATE = app
SOURCES += main.cpp
INCLUDEPATH += /usr/include/ni/
LIBS += /usr/lib/libOpenNI.dylib
In XCode I've dragged libOpenNI.dylib onto the project and ticked the "Copy items into desintation group's folder (if needed)", had /usr/include/ni/ path added to the header search path. Note that depending on what feature you end up using in OpenNI/NITE, you will need to link to other libraries as well (e.g. libnimCodecs,libXnCore,etc.)