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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Hi All,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Could anyone please explain the difference between VTK_IO_EXPORT and VTK_EXPORT (beyond the below definition)? I am writing a file reader plugin and defined my class as VTK_EXPORT. However, many VTK/IO/ reader examples, e.g. vtkAVSucdReader, vtkImageReader are defined as VTK_IO_EXPORT. From the source code,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.0pt;font-family:"Lucida Console";color:#FCAF36;background:black;mso-highlight:black'>#define</span><span style='font-size:9.0pt;font-family:"Lucida Console";color:#EAEAEA;background:black;mso-highlight:black'> VTK_EXPORT VTK_ABI_EXPORT<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.0pt;font-family:"Lucida Console";color:#FCAF36;background:black;mso-highlight:black'>#if</span><span style='font-size:9.0pt;font-family:"Lucida Console";color:#EAEAEA;background:black;mso-highlight:black'> </span><span style='font-size:9.0pt;font-family:"Lucida Console";color:#FCAF36;background:black;mso-highlight:black'>defined</span><span style='font-size:9.0pt;font-family:"Lucida Console";color:#EAEAEA;background:black;mso-highlight:black'>(vtkIO_EXPORTS)<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.0pt;font-family:"Lucida Console";color:gray;background:black;mso-highlight:black'> #define VTK_IO_EXPORT VTK_ABI_EXPORT<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.0pt;font-family:"Lucida Console";color:#EAEAEA;background:black;mso-highlight:black'> </span><span style='font-size:9.0pt;font-family:"Lucida Console";color:#FCAF36;background:black;mso-highlight:black'>#else<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.0pt;font-family:"Lucida Console";color:#EAEAEA;background:black;mso-highlight:black'> </span><span style='font-size:9.0pt;font-family:"Lucida Console";color:#FCAF36;background:black;mso-highlight:black'>#define</span><span style='font-size:9.0pt;font-family:"Lucida Console";color:#EAEAEA;background:black;mso-highlight:black'> VTK_IO_EXPORT VTK_ABI_IMPORT<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Lucida Console";color:#EAEAEA;background:black;mso-highlight:black'> </span><span style='font-size:9.0pt;font-family:"Lucida Console";color:#FCAF36;background:black;mso-highlight:black'>#endif</span><o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thanks for your help.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Best,<o:p></o:p></p><p class=MsoNormal>xunlei<o:p></o:p></p></div></body></html>