Append to INCLUDE environment variable from Visual

Question

I want to append a value to my INCLUDE environment variable. This should be easy.

For example typing

set PATH = "C:/new_entry;%PATH%

works, and can be verified by

echo %PATH%

But doing the same with INCLUDE does not change anything!

Furthermore, INCLUDE is not listed as an environment variable in System Properties > Advanced > Environment Variables, so Visual Studio command prompt is picking it up from somewhere else.

I looked at C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\varsvall.bat, but it is not helpful

@echo off
if "%1" == "" goto x86
if not "%2" == "" goto usage

if /i %1 == x86       goto x86
if /i %1 == amd64     goto amd64
if /i %1 == x64       goto amd64
if /i %1 == arm       goto arm
if /i %1 == x86_arm   goto x86_arm
if /i %1 == x86_amd64 goto x86_amd64
if /i %1 == amd64_x86 goto amd64_x86
if /i %1 == amd64_arm goto amd64_arm
goto usage

:x86
if not exist "%~dp0bin\vcvars32.bat" goto missing
call "%~dp0bin\vcvars32.bat"
goto :SetVisualStudioVersion

:amd64
if not exist "%~dp0bin\amd64\vcvars64.bat" goto missing
call "%~dp0bin\amd64\vcvars64.bat"
goto :SetVisualStudioVersion

:arm
if not exist "%~dp0bin\arm\vcvarsarm.bat" goto missing
call "%~dp0bin\arm\vcvarsarm.bat"
goto :SetVisualStudioVersion

:x86_amd64
if not exist "%~dp0bin\x86_amd64\vcvarsx86_amd64.bat" goto missing
call "%~dp0bin\x86_amd64\vcvarsx86_amd64.bat"
goto :SetVisualStudioVersion

:x86_arm
if not exist "%~dp0bin\x86_arm\vcvarsx86_arm.bat" goto missing
call "%~dp0bin\x86_arm\vcvarsx86_arm.bat"
goto :SetVisualStudioVersion

:amd64_x86
if not exist "%~dp0bin\amd64_x86\vcvarsamd64_x86.bat" goto missing
call "%~dp0bin\amd64_x86\vcvarsamd64_x86.bat"
goto :SetVisualStudioVersion

:amd64_arm
if not exist "%~dp0bin\amd64_arm\vcvarsamd64_arm.bat" goto missing
call "%~dp0bin\amd64_arm\vcvarsamd64_arm.bat"
goto :SetVisualStudioVersion

:SetVisualStudioVersion
set VisualStudioVersion=12.0
goto :eof

:usage
echo Error in script usage. The correct usage is:
echo     %0 [option]
echo where [option] is: x86 ^| amd64 ^| arm ^| x86_amd64 ^| x86_arm ^| amd64_x86 ^| amd64_arm
echo:
echo For example:
echo     %0 x86_amd64
goto :eof

:missing
echo The specified configuration type is missing.  The tools for the
echo configuration might not be installed.
goto :eof

Answer 1

Not Tested with VS 2013

But for older versions: The INCLUDE variable can be defined in machine Environment Variables, but is not required. If it does not exist, then you can create it and define the value as you wish.

Also note that INCLUDE is defined/modified in the sub vcvar*.bat files called within the vcvarsall.bat script.