PEP 3147
diff --git a/Lib/compileall.py b/Lib/compileall.py
index ae86292..d9d7816 100644
--- a/Lib/compileall.py
+++ b/Lib/compileall.py
@@ -12,6 +12,7 @@
 
 """
 import os
+import errno
 import sys
 import py_compile
 import struct
@@ -20,7 +21,7 @@
 __all__ = ["compile_dir","compile_file","compile_path"]
 
 def compile_dir(dir, maxlevels=10, ddir=None,
-                force=0, rx=None, quiet=0):
+                force=False, rx=None, quiet=False, legacy=False):
     """Byte-compile all modules in the given directory tree.
 
     Arguments (only dir is required):
@@ -29,8 +30,9 @@
     maxlevels: maximum recursion level (default 10)
     ddir:      if given, purported directory name (this is the
                directory name that will show up in error messages)
-    force:     if 1, force compilation, even if timestamps are up-to-date
-    quiet:     if 1, be quiet during compilation
+    force:     if True, force compilation, even if timestamps are up-to-date
+    quiet:     if True, be quiet during compilation
+    legacy:    if True, produce legacy pyc paths instead of PEP 3147 paths
 
     """
     if not quiet:
@@ -49,24 +51,26 @@
         else:
             dfile = None
         if not os.path.isdir(fullname):
-            if not compile_file(fullname, ddir, force, rx, quiet):
+            if not compile_file(fullname, ddir, force, rx, quiet, legacy):
                 success = 0
         elif maxlevels > 0 and \
              name != os.curdir and name != os.pardir and \
              os.path.isdir(fullname) and \
              not os.path.islink(fullname):
             if not compile_dir(fullname, maxlevels - 1, dfile, force, rx,
-                               quiet):
+                               quiet, legacy):
                 success = 0
     return success
 
-def compile_file(fullname, ddir=None, force=0, rx=None, quiet=0):
+def compile_file(fullname, ddir=None, force=0, rx=None, quiet=False,
+                 legacy=False):
     """Byte-compile file.
-    file:      the file to byte-compile
+    fullname:  the file to byte-compile
     ddir:      if given, purported directory name (this is the
                directory name that will show up in error messages)
-    force:     if 1, force compilation, even if timestamps are up-to-date
-    quiet:     if 1, be quiet during compilation
+    force:     if True, force compilation, even if timestamps are up-to-date
+    quiet:     if True, be quiet during compilation
+    legacy:    if True, produce legacy pyc paths instead of PEP 3147 paths
 
     """
     success = 1
@@ -80,13 +84,22 @@
         if mo:
             return success
     if os.path.isfile(fullname):
+        if legacy:
+            cfile = fullname + ('c' if __debug__ else 'o')
+        else:
+            cfile = imp.cache_from_source(fullname)
+            cache_dir = os.path.dirname(cfile)
+            try:
+                os.mkdir(cache_dir)
+            except OSError as error:
+                if error.errno != errno.EEXIST:
+                    raise
         head, tail = name[:-3], name[-3:]
         if tail == '.py':
             if not force:
                 try:
                     mtime = int(os.stat(fullname).st_mtime)
                     expect = struct.pack('<4sl', imp.get_magic(), mtime)
-                    cfile = fullname + (__debug__ and 'c' or 'o')
                     with open(cfile, 'rb') as chandle:
                         actual = chandle.read(8)
                     if expect == actual:
@@ -96,14 +109,15 @@
             if not quiet:
                 print('Compiling', fullname, '...')
             try:
-                ok = py_compile.compile(fullname, None, dfile, True)
+                ok = py_compile.compile(fullname, cfile, dfile, True)
             except py_compile.PyCompileError as err:
                 if quiet:
                     print('*** Error compiling', fullname, '...')
                 else:
                     print('*** ', end='')
                 # escape non-printable characters in msg
-                msg = err.msg.encode(sys.stdout.encoding, errors='backslashreplace')
+                msg = err.msg.encode(sys.stdout.encoding,
+                                     errors='backslashreplace')
                 msg = msg.decode(sys.stdout.encoding)
                 print(msg)
                 success = 0
@@ -119,15 +133,17 @@
                     success = 0
     return success
 
-def compile_path(skip_curdir=1, maxlevels=0, force=0, quiet=0):
+def compile_path(skip_curdir=1, maxlevels=0, force=False, quiet=False,
+                 legacy=False):
     """Byte-compile all module on sys.path.
 
     Arguments (all optional):
 
     skip_curdir: if true, skip current directory (default true)
     maxlevels:   max recursion level (default 0)
-    force: as for compile_dir() (default 0)
-    quiet: as for compile_dir() (default 0)
+    force: as for compile_dir() (default False)
+    quiet: as for compile_dir() (default False)
+    legacy: as for compile_dir() (default False)
 
     """
     success = 1
@@ -136,7 +152,8 @@
             print('Skipping current directory')
         else:
             success = success and compile_dir(dir, maxlevels, None,
-                                              force, quiet=quiet)
+                                              force, quiet=quiet,
+                                              legacy=legacy)
     return success
 
 def expand_args(args, flist):
@@ -162,10 +179,10 @@
     """Script main program."""
     import getopt
     try:
-        opts, args = getopt.getopt(sys.argv[1:], 'lfqd:x:i:')
+        opts, args = getopt.getopt(sys.argv[1:], 'lfqd:x:i:b')
     except getopt.error as msg:
         print(msg)
-        print("usage: python compileall.py [-l] [-f] [-q] [-d destdir] " \
+        print("usage: python compileall.py [-l] [-f] [-q] [-d destdir] "
               "[-x regexp] [-i list] [directory|file ...]")
         print("-l: don't recurse down")
         print("-f: force rebuild even if timestamps are up-to-date")
@@ -174,23 +191,27 @@
         print("   if no directory arguments, -l sys.path is assumed")
         print("-x regexp: skip files matching the regular expression regexp")
         print("   the regexp is searched for in the full path of the file")
-        print("-i list: expand list with its content (file and directory names)")
+        print("-i list: expand list with its content "
+              "(file and directory names)")
+        print("-b: Produce legacy byte-compile file paths")
         sys.exit(2)
     maxlevels = 10
     ddir = None
-    force = 0
-    quiet = 0
+    force = False
+    quiet = False
     rx = None
     flist = None
+    legacy = False
     for o, a in opts:
         if o == '-l': maxlevels = 0
         if o == '-d': ddir = a
-        if o == '-f': force = 1
-        if o == '-q': quiet = 1
+        if o == '-f': force = True
+        if o == '-q': quiet = True
         if o == '-x':
             import re
             rx = re.compile(a)
         if o == '-i': flist = a
+        if o == '-b': legacy = True
     if ddir:
         if len(args) != 1 and not os.path.isdir(args[0]):
             print("-d destdir require exactly one directory argument")
@@ -207,13 +228,14 @@
                 for arg in args:
                     if os.path.isdir(arg):
                         if not compile_dir(arg, maxlevels, ddir,
-                                           force, rx, quiet):
+                                           force, rx, quiet, legacy):
                             success = 0
                     else:
-                        if not compile_file(arg, ddir, force, rx, quiet):
+                        if not compile_file(arg, ddir, force, rx,
+                                            quiet, legacy):
                             success = 0
         else:
-            success = compile_path()
+            success = compile_path(legacy=legacy)
     except KeyboardInterrupt:
         print("\n[interrupt]")
         success = 0