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<DIV><SPAN class=375160600-11042007><FONT face=Arial color=#0000ff size=2>Sounds
like this is actually a C problem. int year must be declared in some source file
without the extern. All extern does is tell the compiler and linker "dont worry
you'll find this somewhere eventually" But you lied and to a compiler
too!!!!!</FONT></SPAN></DIV>
<BLOCKQUOTE dir=ltr style="MARGIN-RIGHT: 0px">
<DIV></DIV>
<DIV class=OutlookMessageHeader lang=en-us dir=ltr align=left><FONT
face=Tahoma size=2>-----Original Message-----<BR><B>From:</B>
vtkusers-bounces+paul=opes.com.au@vtk.org
[mailto:vtkusers-bounces+paul=opes.com.au@vtk.org] <B>On Behalf Of </B>Janny
Dong<BR><B>Sent:</B> Tuesday, 10 April 2007 11:06 PM<BR><B>To:</B>
vtkusers@vtk.org<BR><B>Subject:</B> [vtkusers] Cannot use 'extern' keyword in
a project made by Cmake?<BR><BR></FONT></DIV>
<DIV class=Section1>
<P class=MsoNormal><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">Hello
VTKusers,<o:p></o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; 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 face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">‘error LNK2001: unresolved
external symbol “int year” (?year@@3HA)’<o:p></o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; 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 face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">Janny
<o:p></o:p></SPAN></FONT></P></DIV></BLOCKQUOTE></BODY></HTML>