Merged revisions 1767-1783 via svnmerge from

http://scons.tigris.org/svn/scons/branches/core

........
  r1771 | stevenknight | 2007-01-11 10:42:17 -0600 (Thu, 11 Jan 2007) | 1 line

  0.96.D544 - Fix maximum recursion depth exceeded when writing .sconsign files after using Nodes on two different Windows drive letters.
........
  r1772 | stevenknight | 2007-01-11 12:15:07 -0600 (Thu, 11 Jan 2007) | 1 line

  0.96.D545 - Restore caching of file contents in Node.FS.File.get_contents().
........
  r1773 | stevenknight | 2007-01-12 10:22:40 -0600 (Fri, 12 Jan 2007) | 1 line

  0.96.D405 - Add MergeFlags() and AddFlags() methods. (Greg Noel) Support recognizing compiler flags that begin with +. (Kent Boortz)
........
  r1774 | stevenknight | 2007-01-16 15:58:39 -0600 (Tue, 16 Jan 2007) | 2 lines

  Back out previous modification; the wrong change was distributed.
........
  r1775 | stevenknight | 2007-01-16 16:08:26 -0600 (Tue, 16 Jan 2007) | 1 line

  0.96.D546 - Back out previous change that cached get_contents().
........
  r1776 | stevenknight | 2007-01-17 14:30:59 -0600 (Wed, 17 Jan 2007) | 1 line

  0.96.D547 - Document the use of ${} to evaluate arbitrary Python code. (Gary Oberbrunner)
........
  r1777 | stevenknight | 2007-01-17 15:43:18 -0600 (Wed, 17 Jan 2007) | 1 line

  0.96.D548 - Better man page Scanner example (Matt Doar); add FindPathDirs() to the publicly-available functions, and document it.
........
  r1778 | stevenknight | 2007-01-17 17:01:03 -0600 (Wed, 17 Jan 2007) | 1 line

  0.96.D549 - Return MSVC default paths for versions >= 8.0. (Anonymous)
........
  r1779 | stevenknight | 2007-01-18 08:37:58 -0600 (Thu, 18 Jan 2007) | 1 line

  0.96.D550 - Windows fix for the rel_path() unit test.
........
  r1780 | stevenknight | 2007-01-18 14:01:32 -0600 (Thu, 18 Jan 2007) | 1 line

  0.96.D551 - Fix use of __builtins__ in Subst.py.
........
  r1781 | stevenknight | 2007-01-18 16:00:27 -0600 (Thu, 18 Jan 2007) | 1 line

  0.96.D552 - Collect compatibility code in its own SCons.compat subpackage.
........
  r1782 | stevenknight | 2007-01-18 16:22:52 -0600 (Thu, 18 Jan 2007) | 1 line

  0.96.D553 - Add the vanilla Python 2.5 subprocess.py module (currently unused) as a baseline for our backwards-compatibility changes to that module.
........
  r1783 | stevenknight | 2007-01-18 17:09:39 -0600 (Thu, 18 Jan 2007) | 1 line

  0.96.D554 - Change env.ParseConfig() to use the new subprocess module.
........

22 files changed, 2040 insertions, 121 deletions

diff --git a/doc/man/scons.1 b/doc/man/scons.1
index f4bef97..0a76aff 100644
--- a/doc/man/scons.1
+++ b/doc/man/scons.1
@@ -2704,6 +2704,60 @@ foo = env.FindFile('foo', ['dir1', 'dir2'])
 
 '\"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
 .TP
+.RI FindPathDirs( variable )
+Returns a function
+(actually a callable Python object)
+intended to be used as the
+.B path_function
+of a Scanner object.
+The returned object will look up the specified
+.I variable
+in a construction environment
+and treat the construction variable's value as a list of
+directory paths that should be searched
+(like
+.BR CPPPATH ,
+.BR LIBPATH ,
+etc.).
+
+Note that use of
+.BR FindPathDirs ()
+is generally preferable to
+writing your own
+.B path_function
+for the following reasons:
+1) The returned list will contain all appropriate directories
+found in source trees
+(when
+.BR BuildDir ()
+is used)
+or in code repositories
+(when
+.BR Repository ()
+or the
+.B \-Y
+option are used).
+2) scons will identify expansions of
+.I variable
+that evaluate to the same list of directories as,
+in fact, the same list,
+and avoid re-scanning the directories for files,
+when possible.
+
+Example:
+
+.ES
+def my_scan(node, env, path, arg):
+    # Code to scan file contents goes here...
+    return include_files
+
+scanner = Scanner(name = 'myscanner',
+                  function = my_scan,
+                  path_function = FindPathDirs('MYPATH'))
+.EE
+
+'\"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
+.TP
 .RI Flatten( sequence )
 .TP
 .RI env.Flatten( sequence )
@@ -6508,6 +6562,15 @@ ${SOURCE.rsrcpath}   => /usr/repository/src/file.x
 ${SOURCE.rsrcdir}    => /usr/repository/src
 .EE
 
+Note that curly braces braces may also be used
+to enclose arbitrary Python code to be evaluated.
+(In fact, this is how the above modifiers are substituted,
+they are simply attributes of the Python objects
+that represent TARGET, SOURCES, etc.)
+See the section "Python Code Substitution," below,
+for more thorough examples of
+how this can be used.
+
 Lastly, a variable name
 may be a callable Python function
 associated with a
@@ -6603,6 +6666,48 @@ but the command signature added to any target files would be:
 echo Last build occurred  . > $TARGET
 .EE
 
+.SS Python Code Substitution
+
+Any python code within
+.BR "${" - "}"
+pairs gets evaluated by python 'eval', with the python globals set to
+the current environment's set of construction variables.
+So in the following case:
+.ES
+env['COND'] = 0
+env.Command('foo.out', 'foo.in',
+   '''echo ${COND==1 and 'FOO' or 'BAR'} > $TARGET''')
+.EE
+the command executed will be either
+.ES
+echo FOO > foo.out
+.EE
+or
+.ES
+echo BAR > foo.out
+.EE
+according to the current value of env['COND'] when the command is
+executed.  The evaluation occurs when the target is being
+built, not when the SConscript is being read.  So if env['COND'] is changed
+later in the SConscript, the final value will be used.
+
+Here's a more interesting example.  Note that all of COND, FOO, and
+BAR are environment variables, and their values are substituted into
+the final command.  FOO is a list, so its elements are interpolated
+separated by spaces.
+
+.ES
+env=Environment()
+env['COND'] = 0
+env['FOO'] = ['foo1', 'foo2']
+env['BAR'] = 'barbar'
+env.Command('foo.out', 'foo.in',
+    'echo ${COND==1 and FOO or BAR} > $TARGET')
+
+# Will execute this:
+#  echo foo1 foo2 > foo.out
+.EE
+
 SCons uses the following rules when converting construction variables into
 command lines:
 
@@ -6722,6 +6827,12 @@ The
 returns a tuple of directories
 that can be searched for files to be returned
 by this Scanner object.
+(Note that the
+.BR FindPathDirs ()
+function can be used to return a ready-made
+.B path_function
+for a given construction variable name,
+instead of having to write your own function from scratch.)
 
 .IP node_class
 The class of Node that should be returned
@@ -7047,6 +7158,17 @@ env['BUILDERS]['PDFBuilder'] = bld
 
 .SS Defining Your Own Scanner Object
 
+The following example shows an extremely simple scanner (the
+.BR kfile_scan ()
+function)
+that doesn't use a search path at all
+and simply returns the
+file names present on any
+.B include
+lines in the scanned file.
+This would implicitly assume that all included
+files live in the top-level directory:
+
 .ES
 import re
 
@@ -7073,6 +7195,72 @@ env.Command('bar', bar_in, 'kprocess $SOURCES > $TARGET')
 bar_in.target_scanner = kscan
 .EE
 
+Here is a similar but more complete example that searches
+a path of directories
+(specified as the
+.B MYPATH
+construction variable)
+for files that actually exist:
+
+.ES
+include_re = re.compile(r'^include\\s+(\\S+)$', re.M)
+
+def my_scan(node, env, path, arg):
+   contents = node.get_contents()
+   includes = include_re.findall(contents)
+   if includes == []:
+        return []
+    results = []
+    for inc in includes:
+        for dir in path:
+            file = dir + os.sep + inc
+            if os.path.exists(file):  
+                results.append(file)
+                break
+    return results
+
+scanner = Scanner(name = 'myscanner',
+                 function = my_scan,
+                 argument = None,
+                 skeys = ['.x'],
+                 path_function = FindPathDirs('MYPATH'),
+                 )
+scanners = Environment().Dictionary('SCANNERS')
+env = Environment(SCANNERS = scanners + [scanner])
+.EE
+
+The
+.BR FindPathDirs ()
+function used in the previous example returns a function
+(actually a callable Python object)
+that will return a list of directories
+specified in the
+.B $MYPATH
+construction variable.
+If you need to customize how the search path is derived,
+you would provide your own
+.B path_function
+argument when creating the Scanner object,
+as follows:
+
+.ES
+# MYPATH is a list of directories to search for files in
+def pf(env, dir, target, source, arg):
+    top_dir = Dir('#').abspath
+    results = []
+    if env.has_key('MYPATH'):
+        for p in env['MYPATH']:
+            results.append(top_dir + os.sep + p)
+    return results
+
+scanner = Scanner(name = 'myscanner',
+                 function = my_scan,
+                 argument = None,
+                 skeys = ['.x'],
+                 path_function = pf,
+                 )
+.EE
+
 .SS Creating a Hierarchical Build
 
 Notice that the file names specified in a subdirectory's
diff --git a/src/CHANGES.txt b/src/CHANGES.txt
index 711b26c..c4671e5 100644
--- a/src/CHANGES.txt
+++ b/src/CHANGES.txt
@@ -8,6 +8,33 @@
 
 
 
+RELEASE 0.97 - XXX
+
+  From Anonymous:
+
+  - Fix looking for default paths in Visual Studio 8.0 (and later).
+
+  From Matt Doar:
+
+  - Provide a more complete write-your-own-Scanner example in the man page.
+
+  From Steven Knight:
+
+  - Fix the Node.FS.Base.rel_path() method when the two nodes are on
+    different drive letters.  (This caused an infinite loop when
+    trying to write .sconsign files.)
+
+  From Gary Oberbrunner:
+
+  - Document use of ${} to execute arbitrary Python code.
+
+  From John Pye:
+
+  - Change ParseConfig() to preserve white space in arguments passed in
+    as a list.
+
+
+
 RELEASE 0.96.94 - Sun, 07 Jan 2007 18:36:20 -0600
 
   NOTE:  This is a pre-release of 0.97 for testing purposes.
diff --git a/src/engine/MANIFEST.in b/src/engine/MANIFEST.in
index 7be1c16..029217e 100644
--- a/src/engine/MANIFEST.in
+++ b/src/engine/MANIFEST.in
@@ -1,6 +1,10 @@
 SCons/__init__.py
 SCons/Action.py
 SCons/Builder.py
+SCons/compat/__init__.py
+SCons/compat/_subprocess.py
+SCons/compat/_UserString.py
+SCons/compat/builtins.py
 SCons/Conftest.py
 SCons/cpp.py
 SCons/dblite.py
diff --git a/src/engine/SCons/Builder.py b/src/engine/SCons/Builder.py
index d625ed7..51af90b 100644
--- a/src/engine/SCons/Builder.py
+++ b/src/engine/SCons/Builder.py
@@ -103,6 +103,8 @@ There are the following methods for internal use within this module:
 
 __revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
 
+import SCons.compat
+
 import UserDict
 import UserList
 
diff --git a/src/engine/SCons/Environment.py b/src/engine/SCons/Environment.py
index e2883f4..6c392a5 100644
--- a/src/engine/SCons/Environment.py
+++ b/src/engine/SCons/Environment.py
@@ -450,31 +450,28 @@ class SubstitutionEnvironment:
     subst_target_source = subst
 
     def backtick(self, command):
-        try:
-            popen2.Popen3
-        except AttributeError:
-            (tochild, fromchild, childerr) = os.popen3(self.subst(command))
-            tochild.close()
-            err = childerr.read()
-            out = fromchild.read()
-            fromchild.close()
-            status = childerr.close()
+        import subprocess
+        if SCons.Util.is_List(command): 
+            p = subprocess.Popen(command,
+                                 stdout=subprocess.PIPE,
+                                 stderr=subprocess.PIPE,
+                                 universal_newlines=True)
         else:
-            p = popen2.Popen3(command, 1)
-            p.tochild.close()
-            out = p.fromchild.read()
-            err = p.childerr.read()
-            status = p.wait()
+            p = subprocess.Popen(command,
+                                 stdout=subprocess.PIPE,
+                                 stderr=subprocess.PIPE,
+                                 universal_newlines=True,
+                                 shell=True)
+        out = p.stdout.read()
+        p.stdout.close()
+        err = p.stderr.read()
+        p.stderr.close()
+        status = p.wait()
         if err:
             import sys
             sys.stderr.write(err)
         if status:
-            try:
-                if os.WIFEXITED(status):
-                    status = os.WEXITSTATUS(status)
-            except AttributeError:
-                pass
-            raise OSError("'%s' exited %s" % (command, status))
+            raise OSError("'%s' exited %d" % (command, status))
         return out
 
     def Override(self, overrides):
diff --git a/src/engine/SCons/Job.py b/src/engine/SCons/Job.py
index cb8a77a..8dde905 100644
--- a/src/engine/SCons/Job.py
+++ b/src/engine/SCons/Job.py
@@ -31,6 +31,8 @@ stop, and wait on jobs.
 
 __revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
 
+import SCons.compat
+
 class Jobs:
     """An instance of this class initializes N jobs, and provides
     methods for starting, stopping, and waiting on all N jobs.
@@ -153,9 +155,9 @@ else:
                     ok = False
                 except:
                     task.exception_set()
-                    ok = 0
+                    ok = False
                 else:
-                    ok = 1
+                    ok = True
 
                 self.resultsQueue.put((task, ok))
 
@@ -175,7 +177,7 @@ else:
             """Put task into request queue."""
             self.requestQueue.put(obj)
 
-        def get(self, block = 1):
+        def get(self, block = True):
             """Remove and return a result tuple from the results queue."""
             return self.resultsQueue.get(block)
 
diff --git a/src/engine/SCons/Node/FS.py b/src/engine/SCons/Node/FS.py
index 8db2928..9e0e6f6 100644
--- a/src/engine/SCons/Node/FS.py
+++ b/src/engine/SCons/Node/FS.py
@@ -1450,15 +1450,18 @@ class Dir(Base):
         elif not other in self.path_elements:
 
             try:
-                other_dir = other.dir
+                other_dir = other.get_dir()
             except AttributeError:
                 result = str(other)
             else:
-                dir_rel_path = self.rel_path(other_dir)
-                if dir_rel_path == '.':
+                if other_dir is None:
                     result = other.name
                 else:
-                    result = dir_rel_path + os.sep + other.name
+                    dir_rel_path = self.rel_path(other_dir)
+                    if dir_rel_path == '.':
+                        result = other.name
+                    else:
+                        result = dir_rel_path + os.sep + other.name
 
         else:
 
diff --git a/src/engine/SCons/Node/FSTests.py b/src/engine/SCons/Node/FSTests.py
index ec3c322..b9971a2 100644
--- a/src/engine/SCons/Node/FSTests.py
+++ b/src/engine/SCons/Node/FSTests.py
@@ -1473,7 +1473,22 @@ class FSTestCase(_tempdirTestCase):
                 d1_d2_f,        d3_d4_f,        '../../d3/d4/f',
         ]
 
-        d1.rel_path(d3)
+        if sys.platform in ('win32',):
+            x_d1        = fs.Dir(r'X:\d1')
+            x_d1_d2     = x_d1.Dir('d2')
+            y_d1        = fs.Dir(r'Y:\d1')
+            y_d1_d2     = y_d1.Dir('d2')
+            y_d2        = fs.Dir(r'Y:\d2')
+
+            win32_cases = [
+                x_d1,           x_d1,           '.',
+                x_d1,           x_d1_d2,        'd2',
+                x_d1,           y_d1,           r'Y:\d1',
+                x_d1,           y_d1_d2,        r'Y:\d1\d2',
+                x_d1,           y_d2,           r'Y:\d2',
+            ]
+
+            cases.extend(win32_cases)
 
         failed = 0
         while cases:
@@ -1502,6 +1517,8 @@ class FSTestCase(_tempdirTestCase):
         f2 = self.fs.Entry(p)
         assert f1 is f2, (f1, f2)
 
+
+
 class DirTestCase(_tempdirTestCase):
 
     def test__morph(self):
diff --git a/src/engine/SCons/Node/__init__.py b/src/engine/SCons/Node/__init__.py
index e17666b..405010c 100644
--- a/src/engine/SCons/Node/__init__.py
+++ b/src/engine/SCons/Node/__init__.py
@@ -44,7 +44,7 @@ be able to depend on any other type of "thing."
 
 __revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
 
-
+import SCons.compat
 
 import copy
 import string
diff --git a/src/engine/SCons/Script/__init__.py b/src/engine/SCons/Script/__init__.py
index 55797df..067f540 100644
--- a/src/engine/SCons/Script/__init__.py
+++ b/src/engine/SCons/Script/__init__.py
@@ -138,6 +138,7 @@ Builder                 = SCons.Builder.Builder
 Configure               = _SConscript.Configure
 EnumOption              = SCons.Options.EnumOption
 Environment             = SCons.Environment.Environment
+FindPathDirs            = SCons.Scanner.FindPathDirs
 ListOption              = SCons.Options.ListOption
 PackageOption           = SCons.Options.PackageOption
 PathOption              = SCons.Options.PathOption
diff --git a/src/engine/SCons/Subst.py b/src/engine/SCons/Subst.py
index 115f7db..2a993be 100644
--- a/src/engine/SCons/Subst.py
+++ b/src/engine/SCons/Subst.py
@@ -29,11 +29,13 @@ SCons string substitution.
 
 __revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
 
-import __builtin__
+import SCons.compat
+
 import re
 import string
 import types
 import UserList
+import UserString
 
 import SCons.Errors
 
@@ -121,17 +123,15 @@ def quote_spaces(arg):
     else:
         return str(arg)
 
-class CmdStringHolder(SCons.Util.UserString):
+class CmdStringHolder(UserString.UserString):
     """This is a special class used to hold strings generated by
     scons_subst() and scons_subst_list().  It defines a special method
     escape().  When passed a function with an escape algorithm for a
     particular platform, it will return the contained string with the
     proper escape sequences inserted.
-
-    This should really be a subclass of UserString, but that module
-    doesn't exist in Python 1.5.2."""
+    """
     def __init__(self, cmd, literal=None):
-        SCons.Util.UserString.__init__(self, cmd)
+        UserString.UserString.__init__(self, cmd)
         self.literal = literal
 
     def is_literal(self):
@@ -497,18 +497,18 @@ def scons_subst(strSubst, env, mode=SUBST_RAW, target=None, source=None, gvars={
         lvars.update(d)
 
     # We're (most likely) going to eval() things.  If Python doesn't
-    # find a __builtin__ value in the global dictionary used for eval(),
-    # it copies the current __builtin__ values for you.  Avoid this by
+    # find a __builtins__ value in the global dictionary used for eval(),
+    # it copies the current global values for you.  Avoid this by
     # setting it explicitly and then deleting, so we don't pollute the
     # construction environment Dictionary(ies) that are typically used
     # for expansion.
-    gvars['__builtin__'] = __builtin__
+    gvars['__builtins__'] = __builtins__
 
     ss = StringSubber(env, mode, target, source, conv, gvars)
     result = ss.substitute(strSubst, lvars)
 
     try:
-        del gvars['__builtin__']
+        del gvars['__builtins__']
     except KeyError:
         pass
 
@@ -784,8 +784,8 @@ def scons_subst_list(strSubst, env, mode=SUBST_RAW, target=None, source=None, gv
         lvars.update(d)
 
     # We're (most likely) going to eval() things.  If Python doesn't
-    # find a __builtin__ value in the global dictionary used for eval(),
-    # it copies the current __builtin__ values for you.  Avoid this by
+    # find a __builtins__ value in the global dictionary used for eval(),
+    # it copies the current global values for you.  Avoid this by
     # setting it explicitly and then deleting, so we don't pollute the
     # construction environment Dictionary(ies) that are typically used
     # for expansion.
diff --git a/src/engine/SCons/Tool/msvc.py b/src/engine/SCons/Tool/msvc.py
index 7e476f5..5c9eaf0 100644
--- a/src/engine/SCons/Tool/msvc.py
+++ b/src/engine/SCons/Tool/msvc.py
@@ -599,7 +599,7 @@ def get_msvc_default_paths(env, version=None, use_mfc_dirs=0):
     version_num, suite = SCons.Tool.msvs.msvs_parse_version(version)
     if version_num >= 8.0:
         suite = SCons.Tool.msvs.get_default_visualstudio8_suite(env)
-        defpaths = _get_msvc8_default_paths(env, version, suite, use_mfc_dirs)
+        return _get_msvc8_default_paths(env, version, suite, use_mfc_dirs)
     elif version_num >= 7.0:
         return _get_msvc7_default_paths(env, version, use_mfc_dirs)
     else:
diff --git a/src/engine/SCons/Util.py b/src/engine/SCons/Util.py
index d673d22..4bd050a 100644
--- a/src/engine/SCons/Util.py
+++ b/src/engine/SCons/Util.py
@@ -29,7 +29,8 @@ Various utility functions go here.
 
 __revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
 
-import __builtin__
+import SCons.compat
+
 import copy
 import os
 import os.path
@@ -41,6 +42,7 @@ import types
 
 from UserDict import UserDict
 from UserList import UserList
+from UserString import UserString
 
 # Don't "from types import ..." these because we need to get at the
 # types module later to look for UnicodeType.
@@ -50,68 +52,6 @@ ListType        = types.ListType
 StringType      = types.StringType
 TupleType       = types.TupleType
 
-try:
-    from UserString import UserString
-except ImportError:
-    # "Borrowed" from the Python 2.2 UserString module
-    # and modified slightly for use with SCons.
-    class UserString:
-        def __init__(self, seq):
-            if is_String(seq):
-                self.data = seq
-            elif isinstance(seq, UserString):
-                self.data = seq.data[:]
-            else:
-                self.data = str(seq)
-        def __str__(self): return str(self.data)
-        def __repr__(self): return repr(self.data)
-        def __int__(self): return int(self.data)
-        def __long__(self): return long(self.data)
-        def __float__(self): return float(self.data)
-        def __complex__(self): return complex(self.data)
-        def __hash__(self): return hash(self.data)
-
-        def __cmp__(self, string):
-            if isinstance(string, UserString):
-                return cmp(self.data, string.data)
-            else:
-                return cmp(self.data, string)
-        def __contains__(self, char):
-            return char in self.data
-
-        def __len__(self): return len(self.data)
-        def __getitem__(self, index): return self.__class__(self.data[index])
-        def __getslice__(self, start, end):
-            start = max(start, 0); end = max(end, 0)
-            return self.__class__(self.data[start:end])
-
-        def __add__(self, other):
-            if isinstance(other, UserString):
-                return self.__class__(self.data + other.data)
-            elif is_String(other):
-                return self.__class__(self.data + other)
-            else:
-                return self.__class__(self.data + str(other))
-        def __radd__(self, other):
-            if is_String(other):
-                return self.__class__(other + self.data)
-            else:
-                return self.__class__(str(other) + self.data)
-        def __mul__(self, n):
-            return self.__class__(self.data*n)
-        __rmul__ = __mul__
-
-#
-try:
-    __builtin__.zip
-except AttributeError:
-    def zip(*lists):
-        result = []
-        for i in xrange(len(lists[0])):
-            result.append(tuple(map(lambda l, i=i: l[i], lists)))
-        return result
-    __builtin__.zip = zip
-
 _altsep = os.altsep
 if _altsep is None and sys.platform == 'win32':
     # My ActivePython 2.0.1 doesn't set os.altsep!  What gives?
diff --git a/src/engine/SCons/compat/_UserString.py b/src/engine/SCons/compat/_UserString.py
new file mode 100644
index 0000000..4adffa2
--- /dev/null
+++ b/src/engine/SCons/compat/_UserString.py
@@ -0,0 +1,92 @@
+#
+# __COPYRIGHT__
+#
+# Permission is hereby granted, free of charge, to any person obtaining
+# a copy of this software and associated documentation files (the
+# "Software"), to deal in the Software without restriction, including
+# without limitation the rights to use, copy, modify, merge, publish,
+# distribute, sublicense, and/or sell copies of the Software, and to
+# permit persons to whom the Software is furnished to do so, subject to
+# the following conditions:
+#
+# The above copyright notice and this permission notice shall be included
+# in all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY
+# KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
+# WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+#
+
+__revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
+
+__doc__ = """
+A user-defined wrapper around string objects
+
+This class is "borrowed" from the Python 2.2 UserString and modified
+slightly for use with SCons.  It is *NOT* guaranteed to be fully compliant
+with the standard UserString class from all later versions of Python.
+In particular, it does not necessarily contain all of the methods found
+in later versions.
+"""
+
+import types
+
+StringType = types.StringType
+
+if hasattr(types, 'UnicodeType'):
+    UnicodeType = types.UnicodeType
+    def is_String(obj):
+        return type(obj) in (StringType, UnicodeType)
+else:
+    def is_String(obj):
+        return type(obj) is StringType
+
+class UserString:
+    def __init__(self, seq):
+        if is_String(seq):
+            self.data = seq
+        elif isinstance(seq, UserString):
+            self.data = seq.data[:]
+        else:
+            self.data = str(seq)
+    def __str__(self): return str(self.data)
+    def __repr__(self): return repr(self.data)
+    def __int__(self): return int(self.data)
+    def __long__(self): return long(self.data)
+    def __float__(self): return float(self.data)
+    def __complex__(self): return complex(self.data)
+    def __hash__(self): return hash(self.data)
+
+    def __cmp__(self, string):
+        if isinstance(string, UserString):
+            return cmp(self.data, string.data)
+        else:
+            return cmp(self.data, string)
+    def __contains__(self, char):
+        return char in self.data
+
+    def __len__(self): return len(self.data)
+    def __getitem__(self, index): return self.__class__(self.data[index])
+    def __getslice__(self, start, end):
+        start = max(start, 0); end = max(end, 0)
+        return self.__class__(self.data[start:end])
+
+    def __add__(self, other):
+        if isinstance(other, UserString):
+            return self.__class__(self.data + other.data)
+        elif is_String(other):
+            return self.__class__(self.data + other)
+        else:
+            return self.__class__(self.data + str(other))
+    def __radd__(self, other):
+        if is_String(other):
+            return self.__class__(other + self.data)
+        else:
+            return self.__class__(str(other) + self.data)
+    def __mul__(self, n):
+        return self.__class__(self.data*n)
+    __rmul__ = __mul__
diff --git a/src/engine/SCons/compat/__init__.py b/src/engine/SCons/compat/__init__.py
new file mode 100644
index 0000000..6112db5
--- /dev/null
+++ b/src/engine/SCons/compat/__init__.py
@@ -0,0 +1,92 @@
+#
+# __COPYRIGHT__
+#
+# Permission is hereby granted, free of charge, to any person obtaining
+# a copy of this software and associated documentation files (the
+# "Software"), to deal in the Software without restriction, including
+# without limitation the rights to use, copy, modify, merge, publish,
+# distribute, sublicense, and/or sell copies of the Software, and to
+# permit persons to whom the Software is furnished to do so, subject to
+# the following conditions:
+#
+# The above copyright notice and this permission notice shall be included
+# in all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY
+# KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
+# WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+#
+
+__doc__ = """
+SCons compatibility package for old Python versions
+
+This subpackage holds modules that provide backwards-compatible
+implementations of various things that we'd like to use in SCons but which
+only show up in later versions of Python than the early, old version(s)
+we still support.
+
+This package will be imported by other code:
+
+    import SCons.compat
+
+But other code will not generally reference things in this package through
+the SCons.compat namespace.  The modules included here add things to
+the __builtin__ namespace or the global module list so that the rest
+of our code can use the objects and names imported here regardless of
+Python version.
+
+Simply enough, things that go in the __builtin__ name space come from
+our builtins module.
+
+The rest of the things here will be in individual compatibility modules
+that are either: 1) suitably modified copies of the future modules that
+we want to use; or 2) backwards compatible re-implementations of the
+specific portions of a future module's API that we want to use.
+
+GENERAL WARNINGS:  Implementations of functions in the SCons.compat
+modules are *NOT* guaranteed to be fully compliant with these functions in
+later versions of Python.  We are only concerned with adding functionality
+that we actually use in SCons, so be wary if you lift this code for
+other uses.  (That said, making these more nearly the same as later,
+official versions is still a desirable goal, we just don't need to be
+obsessive about it.)
+
+We name the compatibility modules with an initial underscore (for
+example, _subprocess.py is our compatibility module for subprocess)
+so that we can still try to import the real module name and fall back
+to our compatibility module if we get an ImportError.  The import_as()
+function defined below loads the module as the "real" name (without the
+underscore), after which all of the "import {module}" statements in the
+rest of our code will find our pre-loaded compatibility module.
+"""
+
+__revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
+
+def import_as(module, name):
+    """
+    Imports the specified module (from our local directory) as the
+    specified name.
+    """
+    import imp
+    import os.path
+    dir = os.path.split(__file__)[0]
+    file, filename, suffix_mode_type = imp.find_module(module, [dir])
+    imp.load_module(name, file, filename, suffix_mode_type)
+
+import builtins
+
+try:
+    import subprocess
+except ImportError:
+    # Pre-2.4 Python has no subprocess module.
+    import_as('_subprocess', 'subprocess')
+
+try:
+    import UserString
+except ImportError:
+    # Pre-1.6 Python has no UserString module.
+    import_as('_UserString', 'UserString')
diff --git a/src/engine/SCons/compat/_subprocess.py b/src/engine/SCons/compat/_subprocess.py
new file mode 100644
index 0000000..aa17cae
--- /dev/null
+++ b/src/engine/SCons/compat/_subprocess.py
@@ -0,0 +1,1270 @@
+# subprocess - Subprocesses with accessible I/O streams
+#
+# For more information about this module, see PEP 324.
+#
+# This module should remain compatible with Python 2.2, see PEP 291.
+#
+# Copyright (c) 2003-2005 by Peter Astrand <astrand@lysator.liu.se>
+#
+# Licensed to PSF under a Contributor Agreement.
+# See http://www.python.org/2.4/license for licensing details.
+
+r"""subprocess - Subprocesses with accessible I/O streams
+
+This module allows you to spawn processes, connect to their
+input/output/error pipes, and obtain their return codes.  This module
+intends to replace several other, older modules and functions, like:
+
+os.system
+os.spawn*
+os.popen*
+popen2.*
+commands.*
+
+Information about how the subprocess module can be used to replace these
+modules and functions can be found below.
+
+
+
+Using the subprocess module
+===========================
+This module defines one class called Popen:
+
+class Popen(args, bufsize=0, executable=None,
+            stdin=None, stdout=None, stderr=None,
+            preexec_fn=None, close_fds=False, shell=False,
+            cwd=None, env=None, universal_newlines=False,
+            startupinfo=None, creationflags=0):
+
+
+Arguments are:
+
+args should be a string, or a sequence of program arguments.  The
+program to execute is normally the first item in the args sequence or
+string, but can be explicitly set by using the executable argument.
+
+On UNIX, with shell=False (default): In this case, the Popen class
+uses os.execvp() to execute the child program.  args should normally
+be a sequence.  A string will be treated as a sequence with the string
+as the only item (the program to execute).
+
+On UNIX, with shell=True: If args is a string, it specifies the
+command string to execute through the shell.  If args is a sequence,
+the first item specifies the command string, and any additional items
+will be treated as additional shell arguments.
+
+On Windows: the Popen class uses CreateProcess() to execute the child
+program, which operates on strings.  If args is a sequence, it will be
+converted to a string using the list2cmdline method.  Please note that
+not all MS Windows applications interpret the command line the same
+way: The list2cmdline is designed for applications using the same
+rules as the MS C runtime.
+
+bufsize, if given, has the same meaning as the corresponding argument
+to the built-in open() function: 0 means unbuffered, 1 means line
+buffered, any other positive value means use a buffer of
+(approximately) that size.  A negative bufsize means to use the system
+default, which usually means fully buffered.  The default value for
+bufsize is 0 (unbuffered).
+
+stdin, stdout and stderr specify the executed programs' standard
+input, standard output and standard error file handles, respectively.
+Valid values are PIPE, an existing file descriptor (a positive
+integer), an existing file object, and None.  PIPE indicates that a
+new pipe to the child should be created.  With None, no redirection
+will occur; the child's file handles will be inherited from the
+parent.  Additionally, stderr can be STDOUT, which indicates that the
+stderr data from the applications should be captured into the same
+file handle as for stdout.
+
+If preexec_fn is set to a callable object, this object will be called
+in the child process just before the child is executed.
+
+If close_fds is true, all file descriptors except 0, 1 and 2 will be
+closed before the child process is executed.
+
+if shell is true, the specified command will be executed through the
+shell.
+
+If cwd is not None, the current directory will be changed to cwd
+before the child is executed.
+
+If env is not None, it defines the environment variables for the new
+process.
+
+If universal_newlines is true, the file objects stdout and stderr are
+opened as a text files, but lines may be terminated by any of '\n',
+the Unix end-of-line convention, '\r', the Macintosh convention or
+'\r\n', the Windows convention.  All of these external representations
+are seen as '\n' by the Python program.  Note: This feature is only
+available if Python is built with universal newline support (the
+default).  Also, the newlines attribute of the file objects stdout,
+stdin and stderr are not updated by the communicate() method.
+
+The startupinfo and creationflags, if given, will be passed to the
+underlying CreateProcess() function.  They can specify things such as
+appearance of the main window and priority for the new process.
+(Windows only)
+
+
+This module also defines two shortcut functions:
+
+call(*popenargs, **kwargs):
+    Run command with arguments.  Wait for command to complete, then
+    return the returncode attribute.
+
+    The arguments are the same as for the Popen constructor.  Example:
+
+    retcode = call(["ls", "-l"])
+
+check_call(*popenargs, **kwargs):
+    Run command with arguments.  Wait for command to complete.  If the
+    exit code was zero then return, otherwise raise
+    CalledProcessError.  The CalledProcessError object will have the
+    return code in the returncode attribute.
+
+    The arguments are the same as for the Popen constructor.  Example:
+
+    check_call(["ls", "-l"])
+
+Exceptions
+----------
+Exceptions raised in the child process, before the new program has
+started to execute, will be re-raised in the parent.  Additionally,
+the exception object will have one extra attribute called
+'child_traceback', which is a string containing traceback information
+from the childs point of view.
+
+The most common exception raised is OSError.  This occurs, for
+example, when trying to execute a non-existent file.  Applications
+should prepare for OSErrors.
+
+A ValueError will be raised if Popen is called with invalid arguments.
+
+check_call() will raise CalledProcessError, if the called process
+returns a non-zero return code.
+
+
+Security
+--------
+Unlike some other popen functions, this implementation will never call
+/bin/sh implicitly.  This means that all characters, including shell
+metacharacters, can safely be passed to child processes.
+
+
+Popen objects
+=============
+Instances of the Popen class have the following methods:
+
+poll()
+    Check if child process has terminated.  Returns returncode
+    attribute.
+
+wait()
+    Wait for child process to terminate.  Returns returncode attribute.
+
+communicate(input=None)
+    Interact with process: Send data to stdin.  Read data from stdout
+    and stderr, until end-of-file is reached.  Wait for process to
+    terminate.  The optional stdin argument should be a string to be
+    sent to the child process, or None, if no data should be sent to
+    the child.
+
+    communicate() returns a tuple (stdout, stderr).
+
+    Note: The data read is buffered in memory, so do not use this
+    method if the data size is large or unlimited.
+
+The following attributes are also available:
+
+stdin
+    If the stdin argument is PIPE, this attribute is a file object
+    that provides input to the child process.  Otherwise, it is None.
+
+stdout
+    If the stdout argument is PIPE, this attribute is a file object
+    that provides output from the child process.  Otherwise, it is
+    None.
+
+stderr
+    If the stderr argument is PIPE, this attribute is file object that
+    provides error output from the child process.  Otherwise, it is
+    None.
+
+pid
+    The process ID of the child process.
+
+returncode
+    The child return code.  A None value indicates that the process
+    hasn't terminated yet.  A negative value -N indicates that the
+    child was terminated by signal N (UNIX only).
+
+
+Replacing older functions with the subprocess module
+====================================================
+In this section, "a ==> b" means that b can be used as a replacement
+for a.
+
+Note: All functions in this section fail (more or less) silently if
+the executed program cannot be found; this module raises an OSError
+exception.
+
+In the following examples, we assume that the subprocess module is
+imported with "from subprocess import *".
+
+
+Replacing /bin/sh shell backquote
+---------------------------------
+output=`mycmd myarg`
+==>
+output = Popen(["mycmd", "myarg"], stdout=PIPE).communicate()[0]
+
+
+Replacing shell pipe line
+-------------------------
+output=`dmesg | grep hda`
+==>
+p1 = Popen(["dmesg"], stdout=PIPE)
+p2 = Popen(["grep", "hda"], stdin=p1.stdout, stdout=PIPE)
+output = p2.communicate()[0]
+
+
+Replacing os.system()
+---------------------
+sts = os.system("mycmd" + " myarg")
+==>
+p = Popen("mycmd" + " myarg", shell=True)
+pid, sts = os.waitpid(p.pid, 0)
+
+Note:
+
+* Calling the program through the shell is usually not required.
+
+* It's easier to look at the returncode attribute than the
+  exitstatus.
+
+A more real-world example would look like this:
+
+try:
+    retcode = call("mycmd" + " myarg", shell=True)
+    if retcode < 0:
+        print >>sys.stderr, "Child was terminated by signal", -retcode
+    else:
+        print >>sys.stderr, "Child returned", retcode
+except OSError, e:
+    print >>sys.stderr, "Execution failed:", e
+
+
+Replacing os.spawn*
+-------------------
+P_NOWAIT example:
+
+pid = os.spawnlp(os.P_NOWAIT, "/bin/mycmd", "mycmd", "myarg")
+==>
+pid = Popen(["/bin/mycmd", "myarg"]).pid
+
+
+P_WAIT example:
+
+retcode = os.spawnlp(os.P_WAIT, "/bin/mycmd", "mycmd", "myarg")
+==>
+retcode = call(["/bin/mycmd", "myarg"])
+
+
+Vector example:
+
+os.spawnvp(os.P_NOWAIT, path, args)
+==>
+Popen([path] + args[1:])
+
+
+Environment example:
+
+os.spawnlpe(os.P_NOWAIT, "/bin/mycmd", "mycmd", "myarg", env)
+==>
+Popen(["/bin/mycmd", "myarg"], env={"PATH": "/usr/bin"})
+
+
+Replacing os.popen*
+-------------------
+pipe = os.popen(cmd, mode='r', bufsize)
+==>
+pipe = Popen(cmd, shell=True, bufsize=bufsize, stdout=PIPE).stdout
+
+pipe = os.popen(cmd, mode='w', bufsize)
+==>
+pipe = Popen(cmd, shell=True, bufsize=bufsize, stdin=PIPE).stdin
+
+
+(child_stdin, child_stdout) = os.popen2(cmd, mode, bufsize)
+==>
+p = Popen(cmd, shell=True, bufsize=bufsize,
+          stdin=PIPE, stdout=PIPE, close_fds=True)
+(child_stdin, child_stdout) = (p.stdin, p.stdout)
+
+
+(child_stdin,
+ child_stdout,
+ child_stderr) = os.popen3(cmd, mode, bufsize)
+==>
+p = Popen(cmd, shell=True, bufsize=bufsize,
+          stdin=PIPE, stdout=PIPE, stderr=PIPE, close_fds=True)
+(child_stdin,
+ child_stdout,
+ child_stderr) = (p.stdin, p.stdout, p.stderr)
+
+
+(child_stdin, child_stdout_and_stderr) = os.popen4(cmd, mode, bufsize)
+==>
+p = Popen(cmd, shell=True, bufsize=bufsize,
+          stdin=PIPE, stdout=PIPE, stderr=STDOUT, close_fds=True)
+(child_stdin, child_stdout_and_stderr) = (p.stdin, p.stdout)
+
+
+Replacing popen2.*
+------------------
+Note: If the cmd argument to popen2 functions is a string, the command
+is executed through /bin/sh.  If it is a list, the command is directly
+executed.
+
+(child_stdout, child_stdin) = popen2.popen2("somestring", bufsize, mode)
+==>
+p = Popen(["somestring"], shell=True, bufsize=bufsize
+          stdin=PIPE, stdout=PIPE, close_fds=True)
+(child_stdout, child_stdin) = (p.stdout, p.stdin)
+
+
+(child_stdout, child_stdin) = popen2.popen2(["mycmd", "myarg"], bufsize, mode)
+==>
+p = Popen(["mycmd", "myarg"], bufsize=bufsize,
+          stdin=PIPE, stdout=PIPE, close_fds=True)
+(child_stdout, child_stdin) = (p.stdout, p.stdin)
+
+The popen2.Popen3 and popen3.Popen4 basically works as subprocess.Popen,
+except that:
+
+* subprocess.Popen raises an exception if the execution fails
+* the capturestderr argument is replaced with the stderr argument.
+* stdin=PIPE and stdout=PIPE must be specified.
+* popen2 closes all filedescriptors by default, but you have to specify
+  close_fds=True with subprocess.Popen.
+
+
+"""
+
+import sys
+mswindows = (sys.platform == "win32")
+
+import os
+import types
+import traceback
+
+# Exception classes used by this module.
+class CalledProcessError(Exception):
+    """This exception is raised when a process run by check_call() returns
+    a non-zero exit status.  The exit status will be stored in the
+    returncode attribute."""
+    def __init__(self, returncode, cmd):
+        self.returncode = returncode
+        self.cmd = cmd
+    def __str__(self):
+        return "Command '%s' returned non-zero exit status %d" % (self.cmd, self.returncode)
+
+
+if mswindows:
+    import threading
+    import msvcrt
+    if 0: # <-- change this to use pywin32 instead of the _subprocess driver
+        import pywintypes
+        from win32api import GetStdHandle, STD_INPUT_HANDLE, \
+                             STD_OUTPUT_HANDLE, STD_ERROR_HANDLE
+        from win32api import GetCurrentProcess, DuplicateHandle, \
+                             GetModuleFileName, GetVersion
+        from win32con import DUPLICATE_SAME_ACCESS, SW_HIDE
+        from win32pipe import CreatePipe
+        from win32process import CreateProcess, STARTUPINFO, \
+                                 GetExitCodeProcess, STARTF_USESTDHANDLES, \
+                                 STARTF_USESHOWWINDOW, CREATE_NEW_CONSOLE
+        from win32event import WaitForSingleObject, INFINITE, WAIT_OBJECT_0
+    else:
+        from _subprocess import *
+        class STARTUPINFO:
+            dwFlags = 0
+            hStdInput = None
+            hStdOutput = None
+            hStdError = None
+            wShowWindow = 0
+        class pywintypes:
+            error = IOError
+else:
+    import select
+    import errno
+    import fcntl
+    import pickle
+
+    try:
+        fcntl.F_GETFD
+    except AttributeError:
+        fcntl.F_GETFD = 1
+
+    try:
+        fcntl.F_SETFD
+    except AttributeError:
+        fcntl.F_SETFD = 2
+
+__all__ = ["Popen", "PIPE", "STDOUT", "call", "check_call", "CalledProcessError"]
+
+try:
+    MAXFD = os.sysconf("SC_OPEN_MAX")
+except KeyboardInterrupt:
+    raise       # SCons:  don't swallow keyboard interrupts
+except:
+    MAXFD = 256
+
+# True/False does not exist on 2.2.0
+try:
+    False
+except NameError:
+    False = 0
+    True = 1
+
+try:
+    isinstance(1, int)
+except TypeError:
+    def is_int(obj):
+        return type(obj) == type(1)
+    def is_int_or_long(obj):
+        return type(obj) in (type(1), type(1L))
+else:
+    def is_int(obj):
+        return isinstance(obj, int)
+    def is_int_or_long(obj):
+        return isinstance(obj, (int, long))
+
+try:
+    types.StringTypes
+except AttributeError:
+    try:
+        types.StringTypes = (types.StringType, types.UnicodeType)
+    except AttributeError:
+        types.StringTypes = (types.StringType,)
+    def is_string(obj):
+        return type(obj) in types.StringTypes
+else:
+    def is_string(obj):
+        return isinstance(obj, types.StringTypes)
+
+_active = []
+
+def _cleanup():
+    for inst in _active[:]:
+        if inst.poll(_deadstate=sys.maxint) >= 0:
+            try:
+                _active.remove(inst)
+            except ValueError:
+                # This can happen if two threads create a new Popen instance.
+                # It's harmless that it was already removed, so ignore.
+                pass
+
+PIPE = -1
+STDOUT = -2
+
+
+def call(*popenargs, **kwargs):
+    """Run command with arguments.  Wait for command to complete, then
+    return the returncode attribute.
+
+    The arguments are the same as for the Popen constructor.  Example:
+
+    retcode = call(["ls", "-l"])
+    """
+    return apply(Popen, popenargs, kwargs).wait()
+
+
+def check_call(*popenargs, **kwargs):
+    """Run command with arguments.  Wait for command to complete.  If
+    the exit code was zero then return, otherwise raise
+    CalledProcessError.  The CalledProcessError object will have the
+    return code in the returncode attribute.
+
+    The arguments are the same as for the Popen constructor.  Example:
+
+    check_call(["ls", "-l"])
+    """
+    retcode = apply(call, popenargs, kwargs)
+    cmd = kwargs.get("args")
+    if cmd is None:
+        cmd = popenargs[0]
+    if retcode:
+        raise CalledProcessError(retcode, cmd)
+    return retcode
+
+
+def list2cmdline(seq):
+    """
+    Translate a sequence of arguments into a command line
+    string, using the same rules as the MS C runtime:
+
+    1) Arguments are delimited by white space, which is either a
+       space or a tab.
+
+    2) A string surrounded by double quotation marks is
+       interpreted as a single argument, regardless of white space
+       contained within.  A quoted string can be embedded in an
+       argument.
+
+    3) A double quotation mark preceded by a backslash is
+       interpreted as a literal double quotation mark.
+
+    4) Backslashes are interpreted literally, unless they
+       immediately precede a double quotation mark.
+
+    5) If backslashes immediately precede a double quotation mark,
+       every pair of backslashes is interpreted as a literal
+       backslash.  If the number of backslashes is odd, the last
+       backslash escapes the next double quotation mark as
+       described in rule 3.
+    """
+
+    # See
+    # http://msdn.microsoft.com/library/en-us/vccelng/htm/progs_12.asp
+    result = []
+    needquote = False
+    for arg in seq:
+        bs_buf = []
+
+        # Add a space to separate this argument from the others
+        if result:
+            result.append(' ')
+
+        needquote = (" " in arg) or ("\t" in arg)
+        if needquote:
+            result.append('"')
+
+        for c in arg:
+            if c == '\\':
+                # Don't know if we need to double yet.
+                bs_buf.append(c)
+            elif c == '"':
+                # Double backspaces.
+                result.append('\\' * len(bs_buf)*2)
+                bs_buf = []
+                result.append('\\"')
+            else:
+                # Normal char
+                if bs_buf:
+                    result.extend(bs_buf)
+                    bs_buf = []
+                result.append(c)
+
+        # Add remaining backspaces, if any.
+        if bs_buf:
+            result.extend(bs_buf)
+
+        if needquote:
+            result.extend(bs_buf)
+            result.append('"')
+
+    return ''.join(result)
+
+
+try:
+    object
+except NameError:
+    class object:
+        pass
+
+class Popen(object):
+    def __init__(self, args, bufsize=0, executable=None,
+                 stdin=None, stdout=None, stderr=None,
+                 preexec_fn=None, close_fds=False, shell=False,
+                 cwd=None, env=None, universal_newlines=False,
+                 startupinfo=None, creationflags=0):
+        """Create new Popen instance."""
+        _cleanup()
+
+        self._child_created = False
+        if not is_int_or_long(bufsize):
+            raise TypeError("bufsize must be an integer")
+
+        if mswindows:
+            if preexec_fn is not None:
+                raise ValueError("preexec_fn is not supported on Windows "
+                                 "platforms")
+            if close_fds:
+                raise ValueError("close_fds is not supported on Windows "
+                                 "platforms")
+        else:
+            # POSIX
+            if startupinfo is not None:
+                raise ValueError("startupinfo is only supported on Windows "
+                                 "platforms")
+            if creationflags != 0:
+                raise ValueError("creationflags is only supported on Windows "
+                                 "platforms")
+
+        self.stdin = None
+        self.stdout = None
+        self.stderr = None
+        self.pid = None
+        self.returncode = None
+        self.universal_newlines = universal_newlines
+
+        # Input and output objects. The general principle is like
+        # this:
+        #
+        # Parent                   Child
+        # ------                   -----
+        # p2cwrite   ---stdin--->  p2cread
+        # c2pread    <--stdout---  c2pwrite
+        # errread    <--stderr---  errwrite
+        #
+        # On POSIX, the child objects are file descriptors.  On
+        # Windows, these are Windows file handles.  The parent objects
+        # are file descriptors on both platforms.  The parent objects
+        # are None when not using PIPEs. The child objects are None
+        # when not redirecting.
+
+        (p2cread, p2cwrite,
+         c2pread, c2pwrite,
+         errread, errwrite) = self._get_handles(stdin, stdout, stderr)
+
+        self._execute_child(args, executable, preexec_fn, close_fds,
+                            cwd, env, universal_newlines,
+                            startupinfo, creationflags, shell,
+                            p2cread, p2cwrite,
+                            c2pread, c2pwrite,
+                            errread, errwrite)
+
+        if p2cwrite:
+            self.stdin = os.fdopen(p2cwrite, 'wb', bufsize)
+        if c2pread:
+            if universal_newlines:
+                self.stdout = os.fdopen(c2pread, 'rU', bufsize)
+            else:
+                self.stdout = os.fdopen(c2pread, 'rb', bufsize)
+        if errread:
+            if universal_newlines:
+                self.stderr = os.fdopen(errread, 'rU', bufsize)
+            else:
+                self.stderr = os.fdopen(errread, 'rb', bufsize)
+
+
+    def _translate_newlines(self, data):
+        data = data.replace("\r\n", "\n")
+        data = data.replace("\r", "\n")
+        return data
+
+
+    def __del__(self):
+        if not self._child_created:
+            # We didn't get to successfully create a child process.
+            return
+        # In case the child hasn't been waited on, check if it's done.
+        self.poll(_deadstate=sys.maxint)
+        if self.returncode is None and _active is not None:
+            # Child is still running, keep us alive until we can wait on it.
+            _active.append(self)
+
+
+    def communicate(self, input=None):
+        """Interact with process: Send data to stdin.  Read data from
+        stdout and stderr, until end-of-file is reached.  Wait for
+        process to terminate.  The optional input argument should be a
+        string to be sent to the child process, or None, if no data
+        should be sent to the child.
+
+        communicate() returns a tuple (stdout, stderr)."""
+
+        # Optimization: If we are only using one pipe, or no pipe at
+        # all, using select() or threads is unnecessary.
+        if [self.stdin, self.stdout, self.stderr].count(None) >= 2:
+            stdout = None
+            stderr = None
+            if self.stdin:
+                if input:
+                    self.stdin.write(input)
+                self.stdin.close()
+            elif self.stdout:
+                stdout = self.stdout.read()
+            elif self.stderr:
+                stderr = self.stderr.read()
+            self.wait()
+            return (stdout, stderr)
+
+        return self._communicate(input)
+
+
+    if mswindows:
+        #
+        # Windows methods
+        #
+        def _get_handles(self, stdin, stdout, stderr):
+            """Construct and return tupel with IO objects:
+            p2cread, p2cwrite, c2pread, c2pwrite, errread, errwrite
+            """
+            if stdin is None and stdout is None and stderr is None:
+                return (None, None, None, None, None, None)
+
+            p2cread, p2cwrite = None, None
+            c2pread, c2pwrite = None, None
+            errread, errwrite = None, None
+
+            if stdin is None:
+                p2cread = GetStdHandle(STD_INPUT_HANDLE)
+            elif stdin == PIPE:
+                p2cread, p2cwrite = CreatePipe(None, 0)
+                # Detach and turn into fd
+                p2cwrite = p2cwrite.Detach()
+                p2cwrite = msvcrt.open_osfhandle(p2cwrite, 0)
+            elif is_int(stdin):
+                p2cread = msvcrt.get_osfhandle(stdin)
+            else:
+                # Assuming file-like object
+                p2cread = msvcrt.get_osfhandle(stdin.fileno())
+            p2cread = self._make_inheritable(p2cread)
+
+            if stdout is None:
+                c2pwrite = GetStdHandle(STD_OUTPUT_HANDLE)
+            elif stdout == PIPE:
+                c2pread, c2pwrite = CreatePipe(None, 0)
+                # Detach and turn into fd
+                c2pread = c2pread.Detach()
+                c2pread = msvcrt.open_osfhandle(c2pread, 0)
+            elif is_int(stdout):
+                c2pwrite = msvcrt.get_osfhandle(stdout)
+            else:
+                # Assuming file-like object
+                c2pwrite = msvcrt.get_osfhandle(stdout.fileno())
+            c2pwrite = self._make_inheritable(c2pwrite)
+
+            if stderr is None:
+                errwrite = GetStdHandle(STD_ERROR_HANDLE)
+            elif stderr == PIPE:
+                errread, errwrite = CreatePipe(None, 0)
+                # Detach and turn into fd
+                errread = errread.Detach()
+                errread = msvcrt.open_osfhandle(errread, 0)
+            elif stderr == STDOUT:
+                errwrite = c2pwrite
+            elif is_int(stderr):
+                errwrite = msvcrt.get_osfhandle(stderr)
+            else:
+                # Assuming file-like object
+                errwrite = msvcrt.get_osfhandle(stderr.fileno())
+            errwrite = self._make_inheritable(errwrite)
+
+            return (p2cread, p2cwrite,
+                    c2pread, c2pwrite,
+                    errread, errwrite)
+
+
+        def _make_inheritable(self, handle):
+            """Return a duplicate of handle, which is inheritable"""
+            return DuplicateHandle(GetCurrentProcess(), handle,
+                                   GetCurrentProcess(), 0, 1,
+                                   DUPLICATE_SAME_ACCESS)
+
+
+        def _find_w9xpopen(self):
+            """Find and return absolut path to w9xpopen.exe"""
+            w9xpopen = os.path.join(os.path.dirname(GetModuleFileName(0)),
+                                    "w9xpopen.exe")
+            if not os.path.exists(w9xpopen):
+                # Eeek - file-not-found - possibly an embedding
+                # situation - see if we can locate it in sys.exec_prefix
+                w9xpopen = os.path.join(os.path.dirname(sys.exec_prefix),
+                                        "w9xpopen.exe")
+                if not os.path.exists(w9xpopen):
+                    raise RuntimeError("Cannot locate w9xpopen.exe, which is "
+                                       "needed for Popen to work with your "
+                                       "shell or platform.")
+            return w9xpopen
+
+
+        def _execute_child(self, args, executable, preexec_fn, close_fds,
+                           cwd, env, universal_newlines,
+                           startupinfo, creationflags, shell,
+                           p2cread, p2cwrite,
+                           c2pread, c2pwrite,
+                           errread, errwrite):
+            """Execute program (MS Windows version)"""
+
+            if not isinstance(args, types.StringTypes):
+                args = list2cmdline(args)
+
+            # Process startup details
+            if startupinfo is None:
+                startupinfo = STARTUPINFO()
+            if None not in (p2cread, c2pwrite, errwrite):
+                startupinfo.dwFlags = startupinfo.dwFlags | STARTF_USESTDHANDLES
+                startupinfo.hStdInput = p2cread
+                startupinfo.hStdOutput = c2pwrite
+                startupinfo.hStdError = errwrite
+
+            if shell:
+                startupinfo.dwFlags = startupinfo.dwFlags | STARTF_USESHOWWINDOW
+                startupinfo.wShowWindow = SW_HIDE
+                comspec = os.environ.get("COMSPEC", "cmd.exe")
+                args = comspec + " /c " + args
+                if (GetVersion() >= 0x80000000L or
+                        os.path.basename(comspec).lower() == "command.com"):
+                    # Win9x, or using command.com on NT. We need to
+                    # use the w9xpopen intermediate program. For more
+                    # information, see KB Q150956
+                    # (http://web.archive.org/web/20011105084002/http://support.microsoft.com/support/kb/articles/Q150/9/56.asp)
+                    w9xpopen = self._find_w9xpopen()
+                    args = '"%s" %s' % (w9xpopen, args)
+                    # Not passing CREATE_NEW_CONSOLE has been known to
+                    # cause random failures on win9x.  Specifically a
+                    # dialog: "Your program accessed mem currently in
+                    # use at xxx" and a hopeful warning about the
+                    # stability of your system.  Cost is Ctrl+C wont
+                    # kill children.
+                    creationflags = creationflags | CREATE_NEW_CONSOLE
+
+            # Start the process
+            try:
+                hp, ht, pid, tid = CreateProcess(executable, args,
+                                         # no special security
+                                         None, None,
+                                         # must inherit handles to pass std
+                                         # handles
+                                         1,
+                                         creationflags,
+                                         env,
+                                         cwd,
+                                         startupinfo)
+            except pywintypes.error, e:
+                # Translate pywintypes.error to WindowsError, which is
+                # a subclass of OSError.  FIXME: We should really
+                # translate errno using _sys_errlist (or simliar), but
+                # how can this be done from Python?
+                raise apply(WindowsError, e.args)
+
+            # Retain the process handle, but close the thread handle
+            self._child_created = True
+            self._handle = hp
+            self.pid = pid
+            ht.Close()
+
+            # Child is launched. Close the parent's copy of those pipe
+            # handles that only the child should have open.  You need
+            # to make sure that no handles to the write end of the
+            # output pipe are maintained in this process or else the
+            # pipe will not close when the child process exits and the
+            # ReadFile will hang.
+            if p2cread is not None:
+                p2cread.Close()
+            if c2pwrite is not None:
+                c2pwrite.Close()
+            if errwrite is not None:
+                errwrite.Close()
+
+
+        def poll(self, _deadstate=None):
+            """Check if child process has terminated.  Returns returncode
+            attribute."""
+            if self.returncode is None:
+                if WaitForSingleObject(self._handle, 0) == WAIT_OBJECT_0:
+                    self.returncode = GetExitCodeProcess(self._handle)
+            return self.returncode
+
+
+        def wait(self):
+            """Wait for child process to terminate.  Returns returncode
+            attribute."""
+            if self.returncode is None:
+                obj = WaitForSingleObject(self._handle, INFINITE)
+                self.returncode = GetExitCodeProcess(self._handle)
+            return self.returncode
+
+
+        def _readerthread(self, fh, buffer):
+            buffer.append(fh.read())
+
+
+        def _communicate(self, input):
+            stdout = None # Return
+            stderr = None # Return
+
+            if self.stdout:
+                stdout = []
+                stdout_thread = threading.Thread(target=self._readerthread,
+                                                 args=(self.stdout, stdout))
+                stdout_thread.setDaemon(True)
+                stdout_thread.start()
+            if self.stderr:
+                stderr = []
+                stderr_thread = threading.Thread(target=self._readerthread,
+                                                 args=(self.stderr, stderr))
+                stderr_thread.setDaemon(True)
+                stderr_thread.start()
+
+            if self.stdin:
+                if input is not None:
+                    self.stdin.write(input)
+                self.stdin.close()
+
+            if self.stdout:
+                stdout_thread.join()
+            if self.stderr:
+                stderr_thread.join()
+
+            # All data exchanged.  Translate lists into strings.
+            if stdout is not None:
+                stdout = stdout[0]
+            if stderr is not None:
+                stderr = stderr[0]
+
+            # Translate newlines, if requested.  We cannot let the file
+            # object do the translation: It is based on stdio, which is
+            # impossible to combine with select (unless forcing no
+            # buffering).
+            if self.universal_newlines and hasattr(file, 'newlines'):
+                if stdout:
+                    stdout = self._translate_newlines(stdout)
+                if stderr:
+                    stderr = self._translate_newlines(stderr)
+
+            self.wait()
+            return (stdout, stderr)
+
+    else:
+        #
+        # POSIX methods
+        #
+        def _get_handles(self, stdin, stdout, stderr):
+            """Construct and return tupel with IO objects:
+            p2cread, p2cwrite, c2pread, c2pwrite, errread, errwrite
+            """
+            p2cread, p2cwrite = None, None
+            c2pread, c2pwrite = None, None
+            errread, errwrite = None, None
+
+            if stdin is None:
+                pass
+            elif stdin == PIPE:
+                p2cread, p2cwrite = os.pipe()
+            elif is_int(stdin):
+                p2cread = stdin
+            else:
+                # Assuming file-like object
+                p2cread = stdin.fileno()
+
+            if stdout is None:
+                pass
+            elif stdout == PIPE:
+                c2pread, c2pwrite = os.pipe()
+            elif is_int(stdout):
+                c2pwrite = stdout
+            else:
+                # Assuming file-like object
+                c2pwrite = stdout.fileno()
+
+            if stderr is None:
+                pass
+            elif stderr == PIPE:
+                errread, errwrite = os.pipe()
+            elif stderr == STDOUT:
+                errwrite = c2pwrite
+            elif is_int(stderr):
+                errwrite = stderr
+            else:
+                # Assuming file-like object
+                errwrite = stderr.fileno()
+
+            return (p2cread, p2cwrite,
+                    c2pread, c2pwrite,
+                    errread, errwrite)
+
+
+        def _set_cloexec_flag(self, fd):
+            try:
+                cloexec_flag = fcntl.FD_CLOEXEC
+            except AttributeError:
+                cloexec_flag = 1
+
+            old = fcntl.fcntl(fd, fcntl.F_GETFD)
+            fcntl.fcntl(fd, fcntl.F_SETFD, old | cloexec_flag)
+
+
+        def _close_fds(self, but):
+            for i in xrange(3, MAXFD):
+                if i == but:
+                    continue
+                try:
+                    os.close(i)
+                except KeyboardInterrupt:
+                    raise       # SCons:  don't swallow keyboard interrupts
+                except:
+                    pass
+
+
+        def _execute_child(self, args, executable, preexec_fn, close_fds,
+                           cwd, env, universal_newlines,
+                           startupinfo, creationflags, shell,
+                           p2cread, p2cwrite,
+                           c2pread, c2pwrite,
+                           errread, errwrite):
+            """Execute program (POSIX version)"""
+
+            if is_string(args):
+                args = [args]
+
+            if shell:
+                args = ["/bin/sh", "-c"] + args
+
+            if executable is None:
+                executable = args[0]
+
+            # For transferring possible exec failure from child to parent
+            # The first char specifies the exception type: 0 means
+            # OSError, 1 means some other error.
+            errpipe_read, errpipe_write = os.pipe()
+            self._set_cloexec_flag(errpipe_write)
+
+            self.pid = os.fork()
+            self._child_created = True
+            if self.pid == 0:
+                # Child
+                try:
+                    # Close parent's pipe ends
+                    if p2cwrite:
+                        os.close(p2cwrite)
+                    if c2pread:
+                        os.close(c2pread)
+                    if errread:
+                        os.close(errread)
+                    os.close(errpipe_read)
+
+                    # Dup fds for child
+                    if p2cread:
+                        os.dup2(p2cread, 0)
+                    if c2pwrite:
+                        os.dup2(c2pwrite, 1)
+                    if errwrite:
+                        os.dup2(errwrite, 2)
+
+                    # Close pipe fds.  Make sure we don't close the same
+                    # fd more than once, or standard fds.
+                    if p2cread:
+                        os.close(p2cread)
+                    if c2pwrite and c2pwrite not in (p2cread,):
+                        os.close(c2pwrite)
+                    if errwrite and errwrite not in (p2cread, c2pwrite):
+                        os.close(errwrite)
+
+                    # Close all other fds, if asked for
+                    if close_fds:
+                        self._close_fds(but=errpipe_write)
+
+                    if cwd is not None:
+                        os.chdir(cwd)
+
+                    if preexec_fn:
+                        apply(preexec_fn)
+
+                    if env is None:
+                        os.execvp(executable, args)
+                    else:
+                        os.execvpe(executable, args, env)
+
+                except KeyboardInterrupt:
+                    raise       # SCons:  don't swallow keyboard interrupts
+
+                except:
+                    exc_type, exc_value, tb = sys.exc_info()
+                    # Save the traceback and attach it to the exception object
+                    exc_lines = traceback.format_exception(exc_type,
+                                                           exc_value,
+                                                           tb)
+                    exc_value.child_traceback = ''.join(exc_lines)
+                    os.write(errpipe_write, pickle.dumps(exc_value))
+
+                # This exitcode won't be reported to applications, so it
+                # really doesn't matter what we return.
+                os._exit(255)
+
+            # Parent
+            os.close(errpipe_write)
+            if p2cread and p2cwrite:
+                os.close(p2cread)
+            if c2pwrite and c2pread:
+                os.close(c2pwrite)
+            if errwrite and errread:
+                os.close(errwrite)
+
+            # Wait for exec to fail or succeed; possibly raising exception
+            data = os.read(errpipe_read, 1048576) # Exceptions limited to 1 MB
+            os.close(errpipe_read)
+            if data != "":
+                os.waitpid(self.pid, 0)
+                child_exception = pickle.loads(data)
+                raise child_exception
+
+
+        def _handle_exitstatus(self, sts):
+            if os.WIFSIGNALED(sts):
+                self.returncode = -os.WTERMSIG(sts)
+            elif os.WIFEXITED(sts):
+                self.returncode = os.WEXITSTATUS(sts)
+            else:
+                # Should never happen
+                raise RuntimeError("Unknown child exit status!")
+
+
+        def poll(self, _deadstate=None):
+            """Check if child process has terminated.  Returns returncode
+            attribute."""
+            if self.returncode is None:
+                try:
+                    pid, sts = os.waitpid(self.pid, os.WNOHANG)
+                    if pid == self.pid:
+                        self._handle_exitstatus(sts)
+                except os.error:
+                    if _deadstate is not None:
+                        self.returncode = _deadstate
+            return self.returncode
+
+
+        def wait(self):
+            """Wait for child process to terminate.  Returns returncode
+            attribute."""
+            if self.returncode is None:
+                pid, sts = os.waitpid(self.pid, 0)
+                self._handle_exitstatus(sts)
+            return self.returncode
+
+
+        def _communicate(self, input):
+            read_set = []
+            write_set = []
+            stdout = None # Return
+            stderr = None # Return
+
+            if self.stdin:
+                # Flush stdio buffer.  This might block, if the user has
+                # been writing to .stdin in an uncontrolled fashion.
+                self.stdin.flush()
+                if input:
+                    write_set.append(self.stdin)
+                else:
+                    self.stdin.close()
+            if self.stdout:
+                read_set.append(self.stdout)
+                stdout = []
+            if self.stderr:
+                read_set.append(self.stderr)
+                stderr = []
+
+            while read_set or write_set:
+                rlist, wlist, xlist = select.select(read_set, write_set, [])
+
+                if self.stdin in wlist:
+                    # When select has indicated that the file is writable,
+                    # we can write up to PIPE_BUF bytes without risk
+                    # blocking.  POSIX defines PIPE_BUF >= 512
+                    bytes_written = os.write(self.stdin.fileno(), input[:512])
+                    input = input[bytes_written:]
+                    if not input:
+                        self.stdin.close()
+                        write_set.remove(self.stdin)
+
+                if self.stdout in rlist:
+                    data = os.read(self.stdout.fileno(), 1024)
+                    if data == "":
+                        self.stdout.close()
+                        read_set.remove(self.stdout)
+                    stdout.append(data)
+
+                if self.stderr in rlist:
+                    data = os.read(self.stderr.fileno(), 1024)
+                    if data == "":
+                        self.stderr.close()
+                        read_set.remove(self.stderr)
+                    stderr.append(data)
+
+            # All data exchanged.  Translate lists into strings.
+            if stdout is not None:
+                stdout = ''.join(stdout)
+            if stderr is not None:
+                stderr = ''.join(stderr)
+
+            # Translate newlines, if requested.  We cannot let the file
+            # object do the translation: It is based on stdio, which is
+            # impossible to combine with select (unless forcing no
+            # buffering).
+            if self.universal_newlines and hasattr(file, 'newlines'):
+                if stdout:
+                    stdout = self._translate_newlines(stdout)
+                if stderr:
+                    stderr = self._translate_newlines(stderr)
+
+            self.wait()
+            return (stdout, stderr)
+
+
+def _demo_posix():
+    #
+    # Example 1: Simple redirection: Get process list
+    #
+    plist = Popen(["ps"], stdout=PIPE).communicate()[0]
+    print "Process list:"
+    print plist
+
+    #
+    # Example 2: Change uid before executing child
+    #
+    if os.getuid() == 0:
+        p = Popen(["id"], preexec_fn=lambda: os.setuid(100))
+        p.wait()
+
+    #
+    # Example 3: Connecting several subprocesses
+    #
+    print "Looking for 'hda'..."
+    p1 = Popen(["dmesg"], stdout=PIPE)
+    p2 = Popen(["grep", "hda"], stdin=p1.stdout, stdout=PIPE)
+    print repr(p2.communicate()[0])
+
+    #
+    # Example 4: Catch execution error
+    #
+    print
+    print "Trying a weird file..."
+    try:
+        print Popen(["/this/path/does/not/exist"]).communicate()
+    except OSError, e:
+        if e.errno == errno.ENOENT:
+            print "The file didn't exist.  I thought so..."
+            print "Child traceback:"
+            print e.child_traceback
+        else:
+            print "Error", e.errno
+    else:
+        sys.stderr.write( "Gosh.  No error.\n" )
+
+
+def _demo_windows():
+    #
+    # Example 1: Connecting several subprocesses
+    #
+    print "Looking for 'PROMPT' in set output..."
+    p1 = Popen("set", stdout=PIPE, shell=True)
+    p2 = Popen('find "PROMPT"', stdin=p1.stdout, stdout=PIPE)
+    print repr(p2.communicate()[0])
+
+    #
+    # Example 2: Simple execution of program
+    #
+    print "Executing calc..."
+    p = Popen("calc")
+    p.wait()
+
+
+if __name__ == "__main__":
+    if mswindows:
+        _demo_windows()
+    else:
+        _demo_posix()
diff --git a/src/engine/SCons/compat/builtins.py b/src/engine/SCons/compat/builtins.py
new file mode 100644
index 0000000..a477a48
--- /dev/null
+++ b/src/engine/SCons/compat/builtins.py
@@ -0,0 +1,141 @@
+#
+# __COPYRIGHT__
+#
+# Permission is hereby granted, free of charge, to any person obtaining
+# a copy of this software and associated documentation files (the
+# "Software"), to deal in the Software without restriction, including
+# without limitation the rights to use, copy, modify, merge, publish,
+# distribute, sublicense, and/or sell copies of the Software, and to
+# permit persons to whom the Software is furnished to do so, subject to
+# the following conditions:
+#
+# The above copyright notice and this permission notice shall be included
+# in all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY
+# KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
+# WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+#
+
+# Portions of the following are derived from the compat.py file in
+# Twisted, under the following copyright:
+#
+# Copyright (c) 2001-2004 Twisted Matrix Laboratories
+
+__doc__ = """
+Compatibility idioms for __builtin__ names
+
+This module adds names to the __builtin__ module for things that we want
+to use in SCons but which don't show up until later Python versions than
+the earliest ones we support.
+
+This module checks for the following __builtin__ names:
+
+        bool()
+        dict()
+        True
+        False
+        zip()
+
+Implementations of functions are *NOT* guaranteed to be fully compliant
+with these functions in later versions of Python.  We are only concerned
+with adding functionality that we actually use in SCons, so be wary
+if you lift this code for other uses.  (That said, making these more
+nearly the same as later, official versions is still a desirable goal,
+we just don't need to be obsessive about it.)
+
+If you're looking at this with pydoc and various names don't show up in
+the FUNCTIONS or DATA output, that means those names are already built in
+to this version of Python and we don't need to add them from this module.
+"""
+
+__revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
+
+import __builtin__
+
+try:
+    bool
+except NameError:
+    # Pre-2.2 Python has no bool() function.
+    def bool(value):
+        """Demote a value to 0 or 1, depending on its truth value.
+
+        This is not to be confused with types.BooleanType, which is
+        way too hard to duplicate in early Python versions to be
+        worth the trouble.
+        """
+        return not not value
+    __builtin__.bool = bool
+    bool = bool
+
+try:
+    dict
+except NameError:
+    # Pre-2.2 Python has no dict() keyword.
+    def dict(*arg, **kwargs):
+        """
+        New dictionary initialization.
+        """
+        d = apply(types.DictType, arg)
+        d.update(kwargs)
+        return d
+    __builtin__.dict = dict
+
+try:
+    False
+except NameError:
+    # Pre-2.2 Python has no False keyword.
+    __builtin__.False = not 1
+    # Assign to False in this module namespace so it shows up in pydoc output.
+    False = False
+
+try:
+    True
+except NameError:
+    # Pre-2.2 Python has no True keyword.
+    __builtin__.True = not 0
+    # Assign to True in this module namespace so it shows up in pydoc output.
+    True = True
+
+#
+try:
+    zip
+except NameError:
+    # Pre-2.2 Python has no zip() function.
+    def zip(*lists):
+        """
+        Emulates the behavior we need from the built-in zip() function
+        added in Python 2.2.
+
+        Returns a list of tuples, where each tuple contains the i-th
+        element rom each of the argument sequences.  The returned
+        list is truncated in length to the length of the shortest
+        argument sequence.
+        """
+        result = []
+        for i in xrange(min(map(len, lists))):
+            result.append(tuple(map(lambda l, i=i: l[i], lists)))
+        return result
+    __builtin__.zip = zip
+
+
+
+#if sys.version_info[:3] in ((2, 2, 0), (2, 2, 1)):
+#    def lstrip(s, c=string.whitespace):
+#        while s and s[0] in c:
+#            s = s[1:]
+#        return s
+#    def rstrip(s, c=string.whitespace):
+#        while s and s[-1] in c:
+#            s = s[:-1]
+#        return s
+#    def strip(s, c=string.whitespace, l=lstrip, r=rstrip):
+#        return l(r(s, c), c)
+#
+#    object.__setattr__(str, 'lstrip', lstrip)
+#    object.__setattr__(str, 'rstrip', rstrip)
+#    object.__setattr__(str, 'strip', strip)
diff --git a/src/engine/SCons/cpp.py b/src/engine/SCons/cpp.py
index 9bf5779..d96ef23 100644
--- a/src/engine/SCons/cpp.py
+++ b/src/engine/SCons/cpp.py
@@ -27,25 +27,13 @@ __doc__ = """
 SCons C Pre-Processor module
 """
 
+import SCons.compat
+
 import os
 import re
 import string
 import sys
 
-
-
-import __builtin__
-try:
-    __builtin__.zip
-except AttributeError:
-    def zip(*lists):
-        result = []
-        for i in xrange(len(lists[0])):
-            result.append(tuple(map(lambda l, i=i: l[i], lists)))
-        return result
-
-
-
 #
 # First "subsystem" of regular expressions that we set up:
 #
diff --git a/src/setup.py b/src/setup.py
index fa2baf4..9ad0069 100644
--- a/src/setup.py
+++ b/src/setup.py
@@ -354,6 +354,7 @@ arguments = {
     'name'             : "scons",
     'version'          : Version,
     'packages'         : ["SCons",
+                          "SCons.compat",
                           "SCons.Node",
                           "SCons.Optik",
                           "SCons.Options",
diff --git a/src/test_strings.py b/src/test_strings.py
index 2bc951e..9220231 100644
--- a/src/test_strings.py
+++ b/src/test_strings.py
@@ -114,6 +114,7 @@ check_list = [
         'src',
         search_list = [ '*.py' ],
         remove_list = [
+            'engine/SCons/compat/_subprocess.py',
             'engine/SCons/Conftest.py',
             'engine/SCons/dblite.py',
             'engine/SCons/Optik',
@@ -133,6 +134,7 @@ check_list = [
             'configure-stamp',
             'debian',
             'dist',
+            'engine/SCons/compat/_subprocess.py',
             'engine/SCons/Conftest.py',
             'engine/SCons/dblite.py',
             'engine/SCons/Optik',
@@ -145,6 +147,7 @@ check_list = [
     CheckExpandedCopyright(
         build_local,
         remove_list = [
+            'SCons/compat/_subprocess.py',
             'SCons/Conftest.py',
             'SCons/dblite.py',
             'SCons/Optik',
@@ -180,6 +183,7 @@ check_list = [
             'src/engine/MANIFEST.in',
             'src/engine/MANIFEST-xml.in',
             'src/engine/setup.cfg',
+            'src/engine/SCons/compat/_subprocess.py',
             'src/engine/SCons/Conftest.py',
             'src/engine/SCons/dblite.py',
             'src/engine/SCons/Optik',
diff --git a/test/ParseConfig.py b/test/ParseConfig.py
index 668d08a..f142783 100644
--- a/test/ParseConfig.py
+++ b/test/ParseConfig.py
@@ -67,7 +67,7 @@ print env['CCFLAGS']
 
 test.write('SConstruct2', """
 env = Environment(CPPPATH = [], LIBPATH = [], LIBS = [], CCFLAGS = '',
-                  PYTHON = '%(_python_)s')
+                  PYTHON = r'%(_python_)s')
 env.ParseConfig(r"$PYTHON %(test_config1)s --libs --cflags")
 env.ParseConfig(r"$PYTHON %(test_config2)s --libs --cflags")
 print env['CPPPATH']
@@ -78,7 +78,7 @@ print env['CCFLAGS']
 
 test.write('SConstruct3', """
 env = Environment(CPPPATH = [], LIBPATH = [], LIBS = [], CCFLAGS = '',
-                  PYTHON = '%(_python_)s')
+                  PYTHON = r'%(_python_)s')
 env.ParseConfig(r"$PYTHON %(test_config3)s --libs --cflags")
 print env['CPPPATH']
 print env['LIBPATH']
diff --git a/test/Scanner/FindPathDirs.py b/test/Scanner/FindPathDirs.py
new file mode 100644
index 0000000..901d757
--- /dev/null
+++ b/test/Scanner/FindPathDirs.py
@@ -0,0 +1,150 @@
+#!/usr/bin/env python
+#
+# __COPYRIGHT__
+#
+# Permission is hereby granted, free of charge, to any person obtaining
+# a copy of this software and associated documentation files (the
+# "Software"), to deal in the Software without restriction, including
+# without limitation the rights to use, copy, modify, merge, publish,
+# distribute, sublicense, and/or sell copies of the Software, and to
+# permit persons to whom the Software is furnished to do so, subject to
+# the following conditions:
+#
+# The above copyright notice and this permission notice shall be included
+# in all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY
+# KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
+# WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+#
+
+__revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
+
+"""
+Verify that use of the FindPathDirs() function (actually a class)
+can be used to specify a path_function of a scanner.
+"""
+
+import TestSCons
+
+_python_ = TestSCons._python_
+
+test = TestSCons.TestSCons()
+
+test.subdir('inc1', 'inc2')
+
+test.write('build.py', r"""
+import os.path
+import string
+import sys
+path = string.split(sys.argv[1])
+input = open(sys.argv[2], 'rb')
+output = open(sys.argv[3], 'wb')
+
+def find_file(f):
+    for dir in path:
+        p = dir + os.sep + f
+        if os.path.exists(p):
+            return open(p, 'rb')
+    return None
+
+def process(infp, outfp):
+    for line in infp.readlines():
+        if line[:8] == 'include ':
+            file = line[8:-1]
+            process(find_file(file), outfp)
+        else:
+            outfp.write(line)
+
+process(input, output)
+
+sys.exit(0)
+""")
+
+# Execute a subsidiary SConscript just to make sure we can
+# get at the Scanner keyword from there.
+
+test.write('SConstruct', """\
+SConscript('SConscript')
+""")
+
+test.write('SConscript', """\
+import os.path
+import re
+
+include_re = re.compile(r'^include\s+(\S+)$', re.M)
+
+def kfile_scan(node, env, path, arg):
+    contents = node.get_contents()
+    includes = include_re.findall(contents)
+    if includes == []:
+         return []
+    results = []
+    for inc in includes:
+        for dir in path:
+            file = str(dir) + os.sep + inc
+            if os.path.exists(file):  
+                results.append(file)
+                break
+    return results
+
+kscan = Scanner(name = 'kfile',
+                function = kfile_scan,
+                argument = None,
+                skeys = ['.k'],
+                path_function = FindPathDirs('KPATH'))
+
+##########################################################
+# Test scanner as found automatically from the environment
+# (backup_source_scanner)
+
+env = Environment(KPATH=['inc1', 'inc2'])
+env.Append(SCANNERS = kscan)
+
+env.Command('foo', 'foo.k', r'%(_python_)s build.py "$KPATH" $SOURCES $TARGET')
+""" % locals())
+
+
+
+test.write('foo.k', 
+"""foo.k 1 line 1
+include xxx
+include yyy
+foo.k 1 line 4
+""")
+
+test.write(['inc1', 'xxx'], "inc1/xxx 1\n")
+test.write(['inc2', 'yyy'], "inc2/yyy 1\n")
+
+
+
+
+test.run()
+
+test.must_match('foo', "foo.k 1 line 1\ninc1/xxx 1\ninc2/yyy 1\nfoo.k 1 line 4\n")
+
+test.up_to_date(arguments = '.')
+
+
+
+test.write(['inc1', 'xxx'], "inc1/xxx 2\n")
+
+test.run()
+
+test.must_match('foo', "foo.k 1 line 1\ninc1/xxx 2\ninc2/yyy 1\nfoo.k 1 line 4\n")
+
+
+
+test.write(['inc1', 'yyy'], "inc1/yyy 2\n")
+
+test.run()
+
+test.must_match('foo', "foo.k 1 line 1\ninc1/xxx 2\ninc1/yyy 2\nfoo.k 1 line 4\n")
+
+
+
+test.pass_test()