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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Hello VTKusers,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I have been learning how to use VTK with MFC in my visualization
project. VS 2005 is installed on my machine. I succeeded in building all VTK
files and running some examples. When I generated my own project with Cmake, I
couldn’t build it. I declared several variables in my header file using
the keyword ‘extern’. For example, ‘extern int year, month,
day’. In the building process, I kept getting errors like<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>‘error LNK2001: unresolved external symbol “int
year” (?year@@3HA)’<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>When I deleted the word ‘extern’, my project got
built. Anyone has any thoughts? Thanks in advance.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Janny <o:p></o:p></span></font></p>
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