次のプログラムは、Python実行可能パスとサブディレクトリスクリプト（pipやeasy_installがインストールされている場所など）を環境に追加します。.py拡張子をバインドするレジストリキーからPython実行可能ファイルへのパスを見つけます。環境内の古いpythonパスを削除します。XP（おそらくVista）でも動作します。基本的なWindowsインストーラーに付属するモジュールのみを使用します。
# coding: utf-8
import sys
import os
import time
import _winreg
import ctypes
def find_python():
"""
retrieves the commandline for .py extensions from the registry
"""
hKey = _winreg.OpenKey(_winreg.HKEY_CLASSES_ROOT,
r'Python.File\shell\open\command')
# get the default value
value, typ = _winreg.QueryValueEx (hKey, None)
program = value.split('"')[1]
if not program.lower().endswith(r'\python.exe'):
return None
return os.path.dirname(program)
def extend_path(pypath, remove=False, verbose=0, remove_old=True,
script=False):
"""
extend(pypath) adds pypath to the PATH env. variable as defined in the
registry, and then notifies applications (e.g. the desktop) of this change.
!!! Already opened DOS-Command prompts are not updated. !!!
Newly opened prompts will have the new path (inherited from the
updated windows explorer desktop)
options:
remove (default unset), remove from PATH instead of extend PATH
remove_old (default set), removes any (old) python paths first
script (default unset), try to add/remove the Scripts subdirectory
of pypath (pip, easy_install) as well
"""
_sd = 'Scripts' # scripts subdir
hKey = _winreg.OpenKey (_winreg.HKEY_LOCAL_MACHINE,
r'SYSTEM\CurrentControlSet\Control\Session Manager\Environment',
0, _winreg.KEY_READ | _winreg.KEY_SET_VALUE)
value, typ = _winreg.QueryValueEx (hKey, "PATH")
vals = value.split(';')
assert isinstance(vals, list)
if not remove and remove_old:
new_vals = []
for v in vals:
pyexe = os.path.join(v, 'python.exe')
if v != pypath and os.path.exists(pyexe):
if verbose > 0:
print 'removing from PATH:', v
continue
if script and v != os.path.join(pypath, _sd) and \
os.path.exists(v.replace(_sd, pyexe)):
if verbose > 0:
print 'removing from PATH:', v
continue
new_vals.append(v)
vals = new_vals
if remove:
try:
vals.remove(pypath)
except ValueError:
if verbose > 0:
print 'path element', pypath, 'not found'
return
if script:
try:
vals.remove(os.path.join(pypath, _sd))
except ValueError:
pass
print 'removing from PATH:', pypath
else:
if pypath in vals:
if verbose > 0:
print 'path element', pypath, 'already in PATH'
return
vals.append(pypath)
if verbose > 1:
print 'adding to PATH:', pypath
if script:
if not pypath + '\\Scripts' in vals:
vals.append(pypath + '\\Scripts')
if verbose > 1:
print 'adding to PATH:', pypath + '\\Scripts'
_winreg.SetValueEx(hKey, "PATH", 0, typ, ';'.join(vals) )
_winreg.SetValueEx(hKey, "OLDPATH", 0, typ, value )
_winreg.FlushKey(hKey)
# notify other programs
SendMessage = ctypes.windll.user32.SendMessageW
HWND_BROADCAST = 0xFFFF
WM_SETTINGCHANGE = 0x1A
SendMessage(HWND_BROADCAST, WM_SETTINGCHANGE, 0, u'Environment')
if verbose > 1:
print 'Do not forget to restart any command prompts'
if __name__ == '__main__':
remove = '--remove' in sys.argv
script = '--noscripts' not in sys.argv
extend_path(find_python(), verbose=2, remove=remove, script=script)
