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/IDLOUT (Name MIDL Output Files)



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.

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 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 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.

  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