Add to %PATH% before starting another process

CMakeLists.txt

cmake_minimum_required(VERSION 2.8.9)
project(printpath)

add_executable(printpath path.cpp)

set(ENV{PATH} "C:/Some/Path;$ENV{PATH}")

add_custom_target(show "$<TARGET_FILE:printpath>")
add_dependencies(show printpath)

path.cpp

#include <stdio.h>
#include <wchar.h>
#include <windows.h>

int wmain(int argc, wchar_t *argv[])
{
    LPWSTR szValue;
    DWORD size;

    if(!(size = GetEnvironmentVariableW(L"PATH", NULL, 0))) {
        wprintf(L"Unable to determine size to allocate\n");
        return 1;
    }

    szValue = new WCHAR[size];

    if(!GetEnvironmentVariableW(L"PATH", szValue, size)) {
        wprintf(L"Unable to allocate memory\n");
        return 1;
    }

    wprintf(L"Value: %s\n", szValue);
    delete [] szValue;

    return 0;
}