/IDLOUT (Name MIDL Output Files)


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The latest version of this topic can be found at -IDLOUT (Name MIDL Output Files).


## Parameters  
 An absolute or relative path specification. By specifying a path, you affect only the location of an .idl file; all other files are placed in the project directory.  
 Specifies the name of the .idl file created by the MIDL compiler. No file extension is assumed; specify *filename*.idl if you want an .idl extension.  
## Remarks  
 The /IDLOUT option specifies the name and extension of the .idl file.  
 The MIDL compiler is called by the Visual C++ linker when linking projects that have the [module](../Topic/module%20\(C++\).md) attribute.  
 /IDLOUT also specifies the file names of the other output files associated with the MIDL compiler:  
-   *filename*.tlb  
-   *filename*_p.c  
-   *filename*_i.c  
-   *filename*.h  
 *filename* is the parameter that you pass to /IDLOUT. If [/TLBOUT](../Topic/-TLBOUT%20\(Name%20.TLB%20File\).md) is specified, the .tlb file will get its name from /TLBOUT *filename*.  
 If you specify neither /IDLOUT nor /TLBOUT, the linker will create vc70.tlb, vc70.idl, vc70_p.c, vc70_i.c, and vc70.h.  
### 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 **Embedded IDL** property page.  
4.  Modify the **Merge IDL Base File Name** property.  
### To set this linker option programmatically  
-   See [MergedIDLBaseFileName](assetId:///P:Microsoft.VisualStudio.VCProjectEngine.VCLinkerTool.MergedIDLBaseFileName?qualifyHint=False&autoUpgrade=True).  
## See Also  
 [Setting Linker Options](../Topic/Setting%20Linker%20Options.md)   
 [Linker Options](../Topic/Linker%20Options.md)   
 [/IGNOREIDL (Don't Process Attributes into MIDL)](../Topic/-IGNOREIDL%20\(Don't%20Process%20Attributes%20into%20MIDL\).md)   
 [/MIDL (Specify MIDL Command Line Options)](../Topic/-MIDL%20\(Specify%20MIDL%20Command%20Line%20Options\).md)   
 [Building an Attributed Program](../Topic/Building%20an%20Attributed%20Program.md)