What is the Windows equivalent of pwd.getpwnam(username).pw_dir?

Question

The Python pwd module provides access to getpwnam(3) POSIX API, which can be used to get the home directory for a particular user by username, as well determining if the username is valid at all. pwd.getpwnam will raise an exception if called with a non-existent username.

At first it seems like the same result can be achieved in a cross-platform manner via os.path.expanduser('~username'). However, it appears that with Python 2.6 on Windows XP this won't actually produce a failure for a non-existent username. Furthermore, on Python 2.5 on Windows XP, it seems to fail even for valid users.

Can this information be obtained reliably on Windows? How?

Answer 1

you could go the win32api.GetUserName() (current user only) or win32net.NetUserGetInfo() (any user on any server, localhost included) route. the latter could be a bit slow since it can take some time to get this information back from the OS.

  import win32net

  def userDir(username):
        return win32net.NetUserGetInfo(None, username, 1).get("home_dir")

alternatively you could expand the environment variable USERPROFILE on windows or HOME on unix to get the information about the currently logged in user:

  def userDir():
      if os.platform.system() == 'Windows':
          return os.environ['USERPROFILE']
      elif os.platform.system() == 'Linux':
          return os.environ['HOME'] 
      else:
          return None

Answer 2

Reading the 2.6 documentation shows that os.path.expanduser() is broken on Windows:

On Windows, HOME and USERPROFILE will be used if set, otherwise a combination of HOMEPATH and HOMEDRIVE will be used. An initial ~user is handled by stripping the last directory component from the created user path derived above.

Say whaat? This assumes all user homes have to be under the same parent directory. Nuh-ugh!

It was a bit hard to dig but here is a solution that will look up a local user by given name:

from win32security import LookupAccountName, ConvertSidToStringSid
from _winreg import OpenKey, QueryValueEx, HKEY_LOCAL_MACHINE

def getUserDir(userName):
    ssid = ConvertSidToStringSid(LookupAccountName(None, userName)[0])
    key = OpenKey(HKEY_LOCAL_MACHINE, r'SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList\\' + ssid)
    return QueryValueEx(key, 'ProfileImagePath')[0]

Answer 3

This seems to be only applicable to the current user, but on my (winxp) machine, os.path.expanduser('~') returns my home directory.