import logging
import msvcrt
import _subprocess
import os

def duplicate(handle, inheritable=False):
    target_process = _subprocess.GetCurrentProcess()
    return _subprocess.DuplicateHandle(
        _subprocess.GetCurrentProcess(), handle, target_process,
        0, inheritable, _subprocess.DUPLICATE_SAME_ACCESS).Detach()

class NoInheritRotatingFileHandler(logging.handlers.RotatingFileHandler):
    def _open(self):
        """
        Open the current base file with the (original) mode and encoding.
        Return the resulting stream.
        """
        if self.encoding is None:
            stream = open(self.baseFilename, self.mode)
            newosf = duplicate(msvcrt.get_osfhandle(stream.fileno()), inheritable=False)
            newFD  = msvcrt.open_osfhandle(newosf,os.O_APPEND)
            newstream = os.fdopen(newFD,self.mode)
            stream.close()
            return newstream
        else:
            stream = codecs.open(self.baseFilename, self.mode, self.encoding)
        return stream