commit 716cffb2888bb2a0fa3264a22085caf8ce26368f
Author: Pedro Asad <pasad@cos.ufrj.br>
Date:   Wed Oct 8 18:18:57 2014 -0300

    Added a missing -lpthread flag to one Makefile
    
      The lack of the -lpthread flag on Source/Tools/NiViewer/Makefile prevented the
      whole project from compiling correctly on Ubuntu 14.04 64 bit. Just added the
      missing flag to this Makefile, according to the same solution for issue 47 of
      the old OpenNI2 Github repository, that boils down to a similar problem and
      can be found here, on Github
      https://github.com/OpenNI/OpenNI2/issues/47

diff --git a/Source/Tools/NiViewer/Makefile b/Source/Tools/NiViewer/Makefile
index 1eba049..1b5714d 100644
--- a/Source/Tools/NiViewer/Makefile
+++ b/Source/Tools/NiViewer/Makefile
@@ -26,7 +26,7 @@ else
 endif
 
 LIB_DIRS  += ../../../ThirdParty/PSCommon/XnLib/Bin/$(PLATFORM)-$(CFG)
-USED_LIBS += OpenNI2 XnLib
+USED_LIBS += OpenNI2 XnLib pthread
 
 EXE_NAME = NiViewer