Boost
  C++ Libraries
  
  ...one of the most highly
  regarded and expertly designed C++ library projects in the
  world.
 — Herb Sutter and Andrei
  Alexandrescu, C++
  Coding Standards
Boost.Build's msvc toolset supports the Microsoft Visual C++ command-line tools on Microsoft Windows. It supports any version of Visual C++, but in case you have more than one version of Visual C++ installed, and you want to use both, the additional vc7 toolset can be used for Visual C++ 7.0.
msvc toolset responds to the following
  variables, which can be set in the environment or configured on the jam
  command-line using -sVARIABLE_NAME=value:
  | Variable Name | Semantics | Default | Notes | 
|---|---|---|---|
MSVC_ROOT | 
      The path to the MSVC installation directory | 
      c:\Program Files\Microsoft Visual Studio\VC98 | 
      If MSVCDir is set in the environment, the toolset will
      assume VCVARS32.BAThas already been called, and will
      ignore this variable. | 
    
VISUALC | 
      The path to the MSVC installation directory | 
      c:\Program Files\Microsoft Visual C++\VC98 | 
      If MSVCDir or MSVC_ROOT is set in the
      environment, the toolset will assume VCVARS32.BAThas
      already been called, and will ignore this variable. | 
    
Revised 14 May, 2002
Distributed under the Boost Software License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at www.boost.org/LICENSE_1_0.txt)