Besides the “bling”, notable changes include the Visual C++ 2010 CRT reverting to the traditional deployment model used by the Visual C++ 2003 CRT. More specifically, the CRT DLLs no longer use SxS binding (“Fusion”) and are now simply deployed to the “system32″ directory or to the application’s directory, as desired. Dropping SxS has some obvious disadvantages (SxS binding redirects would no longer be able to redirect applications that load a private copy of the CRT DLLs to updated versions with bug fixes and security updates) but presumably the pain of integrating SxS deployment into the setup process, which required either an MSI installation or pseudo-documented use of the SxS API, resulted in too much negative feedback and they chose to revert to the legacy approach.

// Initialize PATH environment variable for current process

typedef std::basic_string<TCHAR, std::char_traits<TCHAR>, std::allocator<TCHAR> > String_t;
typedef boost::scoped_array<TCHAR> TCharBuff_t;

String_t addDirPath = "С:\\Program Files\\Dazdraperma";

DWORD pathBufferSize = ::GetEnvironmentVariable(_T("PATH"), NULL, 0L);
pathBufferSize += addDirPath.length() + 3;

TCharBuff_t pathBuffer(new TCHAR[pathBufferSize]);
ZeroMemory(pathBuffer.get(), pathBufferSize * sizeof(TCHAR));

DWORD getEnvRet = ::GetEnvironmentVariable(_T("PATH"), pathBuffer.get(), pathBufferSize);

if ( getEnvRet )
{
    _tcscat(pathBuffer.get(), _T(";"));
    _tcscat(pathBuffer.get(), addDirPath.c_str());
    _tcscat(pathBuffer.get(), _T(";"));

    BOOL setEnvRet = ::SetEnvironmentVariable(_T("PATH"), pathBuffer.get());

    if ( NULL == setEnvRet )
    {
        // write Win 32 API error to LOG
    }
}
else
{
    // write Win 32 API error to LOG
}

C>>Посматривал в сторону всяких SearchPath, но руки так и не дошли. Собсна отсюда и вопрос: а туда ли я полез? И нету ли способа попроще, а то так и хочется исходник переименовать в "Ничего_Не_Трогайте_НИКОГДА.h"

R>// Initialize PATH environment variable for current process

R>typedef std::basic_string<TCHAR, std::char_traits<TCHAR>, std::allocator<TCHAR> > String_t;
R>typedef boost::scoped_array<TCHAR> TCharBuff_t;

R>String_t addDirPath = "С:\\Program Files\\Dazdraperma";

R>DWORD pathBufferSize = ::GetEnvironmentVariable(_T("PATH"), NULL, 0L);
R>pathBufferSize += addDirPath.length() + 3;

R>TCharBuff_t pathBuffer(new TCHAR[pathBufferSize]);
R>ZeroMemory(pathBuffer.get(), pathBufferSize * sizeof(TCHAR));

R>DWORD getEnvRet = ::GetEnvironmentVariable(_T("PATH"), pathBuffer.get(), pathBufferSize);

R>if ( getEnvRet )
R>{
R>    _tcscat(pathBuffer.get(), _T(";"));
R>    _tcscat(pathBuffer.get(), addDirPath.c_str());
R>    _tcscat(pathBuffer.get(), _T(";"));

R>    BOOL setEnvRet = ::SetEnvironmentVariable(_T("PATH"), pathBuffer.get());

R>    if ( NULL == setEnvRet )
R>    {
R>        // write Win 32 API error to LOG
R>    }
R>}
R>else
R>{
R>    // write Win 32 API error to LOG
R>}
R>

class CAutoDirectory {
CString m_strPrevDir;
operator new();//new - в private его батеньку, в private чтобы никто и никогда и ни при каких! 
public:
//конструктор изменяет текущую директорию
//и запоминает предыдущую
CAutoDirectory(CString strNewDir)
{
GetCurrentDirectory(m_strPrevDir);
SetCurrentDirectory(strNewDir);
}
//деструктор ставит обратно предыдущую директорию
~CAutoDirectory()
{
SetCurrentDirectory(m_strPrevDir);
};

//ну и в коде понеслось
//объявляем на стеке, деструктор сам все вернет на круги своя
CAutoDirectory directory_owner(strNewDir);