nwnc.py 文件源码

def os_id_index():
    """Get the index of the machine OS in the `OS_ID` tuple.

    The `OS_ID` tuple contains the major and minor version of all
    affected Windows versions.  These are matched against
    the major and minor version of `sys.getwindowsversion()`.

    For Windows 8.1 and above `sys.getwindowsversion()` doesn't
    report the correct value, these systems are handled specially. 

    Windows 8 and Server 2012 are special cased because the have the
    same version numbers but require different KBs.

    :return: The index of the operating system in `OS_ID`.
    :rtype: int
    """
    winver = sys.getwindowsversion()
    # sys.getwindowsversion is not enough by itself as the underlying
    # API has been deprecated.  Only applications which have been
    # developed specifically for Windows 8.1 and above, and write that
    # into their manifest file get the correct Windows version on those
    # systems.  Other applications (Python doesn't have the manifest)
    # get a version that pretends to be Windows 8 (major=6, minor=2).
    # See:
    # https://msdn.microsoft.com/en-us/library/windows/desktop/ms724834.aspx
    major, minor = winver.major, winver.minor
    if (major, minor) == (6, 2):
        # Determine if this system is a newer version than Windows 8 by
        # parsing the version string in `platform.win32_ver()[1]`:
        major, minor = tuple(map(int, platform.win32_ver()[1].split('.')[:2]))
    for i, os_id in enumerate(OS_ID):
        if os_id[:2] == (major, minor):
            if len(os_id) == 2:
                return i
            # else evaluate the third item if present which is a lambda:
            if os_id[2]():
                return i
            # otherwise continue with the next item