x-ignore-standard-include-paths.md

description	title	ms.date	f1_keywords	helpviewer_keywords	ms.assetid
Learn more about: `/X` (Ignore standard include paths)	/X (Ignore standard include paths)	01/21/2021	/x VC.Project.VCCLCompilerTool.OVERWRITEStandardIncludePath VC.Project.VCCLWCECompilerTool.OVERWRITEStandardIncludePath VC.Project.VCCLCompilerTool.IgnoreStandardIncludePath	/X compiler option [C++] include files, ignore standard path -X compiler option [C++] include directories, ignore standard X compiler option Ignore Standard Include Paths compiler option	16bdf2cc-c8dc-46e4-bdcc-f3caeba5e1ef

/X (Ignore standard include paths)

Prevents the compiler from searching for include files in directories specified in the PATH and INCLUDE environment variables.

Syntax

/X

Remarks

You can use this option with the /I (Additional include directories) option to specify an alternate path to the standard include files.

To set this compiler option in the Visual Studio development environment

1. Open the project's Property Pages dialog box. For details, see Set C++ compiler and build properties in Visual Studio.

2. Select the Configuration Properties > C/C++ > Preprocessor property page.

3. Modify the Ignore Standard Include Path property.

To set this compiler option programmatically

• See xref:Microsoft.VisualStudio.VCProjectEngine.VCCLCompilerTool.IgnoreStandardIncludePath%2A.

Example

In the following command, /X tells the compiler to ignore locations specified by the PATH and INCLUDE environment variables, and /I specifies the directory to look in for include files:

CL /X /I \ALT\INCLUDE MAIN.C

See also

MSVC compiler options
MSVC compiler command-line syntax