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/DEF (Specify Module-Definition File)


The latest version of this topic can be found at -DEF (Specify Module-Definition File).


## Remarks  
 The name of a module-definition file (.def) to be passed to the linker.  
## Remarks  
 The /DEF option passes a module-definition file (.def) to the linker. Only one .def file can be specified to LINK. For details about .def files, see [Module-Definition Files](../Topic/Module-Definition%20\(.Def\)%20Files.md).  
### To set this linker option in the Visual Studio development environment  
1.  Open the project's **Property Pages** dialog box. For details, see [Setting Visual C++ Project Properties](../Topic/Working%20with%20Project%20Properties.md).  
2.  Click the **Linker** folder.  
3.  Click the **Input** property page.  
4.  Modify the **Module Definition File** property.  
 To specify a .def file from within the development environment, you should add it to the project along with other files and then specify the file to the /DEF option.  
### To set this linker option programmatically  
-   See [ModuleDefinitionFile](assetId:///P:Microsoft.VisualStudio.VCProjectEngine.VCLinkerTool.ModuleDefinitionFile?qualifyHint=False&autoUpgrade=True).  
## See Also  
 [Setting Linker Options](../Topic/Setting%20Linker%20Options.md)   
 [Linker Options](../Topic/Linker%20Options.md)