diff -r 10eaab5887cd Lib/shutil.py
--- a/Lib/shutil.py	Mon Apr 23 14:25:19 2012 +0800
+++ b/Lib/shutil.py	Mon Apr 23 18:24:58 2012 +0800
@@ -822,7 +822,7 @@
     def disk_usage(path):
         """Return disk usage statistics about the given path.
 
-        Returned valus is a named tuple with attributes 'total', 'used' and
+        Returned value is a named tuple with attributes 'total', 'used' and
         'free', which are the amount of total, used and free space, in bytes.
         """
         st = os.statvfs(path)
@@ -921,3 +921,95 @@
             lines = size.lines
 
     return os.terminal_size((columns, lines))
+
+def launch(path, operation='open', gui=True, fallback=True):
+    """Open file with the application that the OS associates with the file-type
+    
+    `path` is the path to the file or directory to open
+    
+    `operation` is the desired application action. Only 'open' is fully 
+    supported. For Windows (and any OS that implements os.startfile), 
+    'edit', 'print', 'explore', are supported. The operation 'find' is 
+    supported on Windows if `path` is to a directory. If not, the containing 
+    folder/directory for the path is used for the os.startfile 'find' operation.
+    
+    `gui` indicates the caller's preference for launching a GUI application 
+    rather than an application with a command-line interface. NOT IMPLEMENTED
+    
+    Fallback controls whether launch() falls back gracefully to less prefered
+    application options--to a nonGUI application if no GUI application
+    is found, or to a viewer application if no edit application can be found.
+    
+    On Windows, calls os.startfile(), and attempts to call it first, 
+    irrespective of os.name or system.platform.
+    
+    On Mac OS X, uses the ```open <https://developer.apple.com/library/mac/#documentation/Darwin/Reference/ManPages/man1/open.1.html>`_`` command.
+    
+    On non-Mac Unix, uses the ```xdg-open <http://portland.freedesktop.org/xdg-utils-1.0/xdg-open.html>`_`` command and fails
+    if it can't be run (e.g., when it's not installed).
+    
+    :raises NotImplementedError: on non-Mac Unix when ``xdg-open`` fails
+    :raises IOError: with *:attr:`errno` = :data:`errno.ENOENT`*, when path doesn't exist
+    :raises OSError: with *:attr:`errno` = :data:`errno.ENOSYS`*, when OS cannot find an appropriate application association
+    
+    :returns: None
+    
+    Example:
+    >>> launch('README')
+    """
+    
+    # FIXME: Is OSError(errno.ENOSYS) the right error to raise?
+    # TODO: Utilize best-practices from Mercurial project:
+    #    http://selenic.com/repo/hg-stable/file/2770d03ae49f/mercurial/ui.py
+    #    http://selenic.com/repo/hg-stable/file/2770d03ae49f/mercurial/util.py
+    
+    import sys, os, subprocess, errno
+
+    # Ensure cross-platform path (Windows-friendly)
+    path = os.path.normpath(path)
+    
+    # Guess user's desired operation (Windows verb)
+    operation = operation or 'open'
+    # Force case and padding to comply with Windows verb specification
+    operation = operation.strip().lower()
+    # Too presumptive, and wouldn't help for most typos ???
+    # operation = operation[:min(len(operation),7]
+
+    # if os.name == 'nt' or sys.platform.startswith('win32') ???
+    if hasattr(os,'startfile') and hasattr(os.startfile, '__call__'):
+        os.startfile(path, operation)
+    elif sys.platform.startswith('darwin'): # or os.name == 'mac' ???
+        # https://developer.apple.com/library/mac/#documentation/Darwin/Reference/ManPages/man1/open.1.html
+        proc = subprocess.Popen( ['open', path], stderr=subprocess.PIPE, 
+                                 stdin=subprocess.DEVNULL, 
+                                 stdout=subprocess.DEVNULL)
+        _, stderr_output = proc.communicate()
+        if proc.returncode:
+            if stderr_output.endswith("does not exist."):
+                raise IOError(errno.ENOENT, "The path %s does not exist" %
+                                              repr(path), path) from err
+            elif stderr_output.startswith("No application can open"):
+                raise OSError(errno.ENOSYS, 
+                              "No application associated with file type in",
+                              path) from err
+    elif os.name == 'posix':
+        try:
+            subprocess.check_call(['xdg-open', path], 
+                                  stdin=subprocess.DEVNULL,
+                                  stdout=subprocess.DEVNULL, 
+                                  stderr=subprocess.DEVNULL)
+        except subprocess.CalledProcessError as err:
+            # http://portland.freedesktop.org/xdg-utils-1.0/xdg-open.html manpage for return code meanings
+            if err.returncode == 2:
+                raise IOError(errno.ENOENT, "Path %s does not exist" % repr(path), path) from err
+            elif err.returncode == 3:
+                raise OSError(errno.ENOSYS, 
+                              "No application associated with file type in",
+                              path) from err
+            else:
+                raise
+        except EnvironmentError as err:
+            if err.errno == errno.ENOENT: # xdg-open not installed/accessible
+                raise NotImplementedError from err 
+            else:
+                raise