/IDLOUT (Name MIDL Output Files)


For the latest documentation on Visual Studio 2017, see Visual Studio 2017 Documentation.

For the latest documentation on Visual Studio 2017, see -IDLOUT (Name MIDL Output Files) on docs.microsoft.com.


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

Setting Linker Options
Linker Options
/IGNOREIDL (Don't Process Attributes into MIDL)
/MIDL (Specify MIDL Command Line Options)
Building an Attributed Program