Here is a list of all files with brief descriptions:

Include
IXnNodeAllocator.h
XnAlgorithms.h
XnArray.h
XnBaseNode.h
XnBitSet.h
XnCallback.h
XnCodecIDs.h
XnContext.h
XnCppWrapper.h
XnCyclicQueueT.h
XnCyclicStackT.h
XnDataTypes.h
XnDerivedCast.h
XnDump.h
XnDumpWriters.h
XnEnumerationErrors.h
XnEvent.h
XnEventT.h
XnFPSCalculator.h
XnGeneralBuffer.h
XnHash.h
XnHashT.h
XnInternalDefs.h
XnLicensing.h
XnList.h
XnListT.h
XnLog.h
XnLogTypes.h
XnLogWriterBase.h
XnMacros.h
XnModuleCFunctions.h
XnModuleCppInterface.h
XnModuleCppRegistratration.h
XnModuleInterface.h
XnNode.h
XnNodeAllocator.h
XnOpenNI.h
XnOS.h
XnOSCpp.h
XnOSMemory.h
XnOSStrings.h
XnPlatform.h
XnPrdNode.h
XnPrdNodeInfo.h
XnPrdNodeInfoList.h
XnProfiling.h
XnPropNames.h
XnQueries.h
XnQueue.h
XnQueueT.h
XnScheduler.h
XnStack.h
XnStackT.h
XnStatus.h
XnStatusCodes.h
XnStatusRegister.h
XnStringsHash.h
XnStringsHashT.h
XnThreadSafeQueue.h
XnTypes.h
XnUSB.h
XnUSBDevice.h
XnUtils.h
XnVersion.h
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