[Zope] getting filename cross platform

[John Hunter]

I have a file upload form which gets a filename from the local file
system and then passes it to a Python Script which adds the file to
the Zope filesystem and returns the filename.  I want to return just the
filename with the local path information stripped off.  This works
fine when the file is uploaded from Linux, but not when it is uploaded
from Microsoft Windows.

Here is the python script

  ## Script (Python) "add_to_filesystem_py"
  ##bind container=container
  ##bind context=context
  ##bind namespace=
  ##bind script=script
  ##bind subpath=traverse_subpath
  ##parameters=folder_name,file_name
  ##title=
  ##

  REQUEST = container.REQUEST
  RESPONSE =  REQUEST.RESPONSE

  idFolder = getattr(context.Patients, REQUEST.get('pid'))
  folder = getattr(idFolder, folder_name)
  folder.manage_addFile(id='', file=file_name)
  return getattr(file_name, 'filename')

If pid, the patient id, is '1234', folder_name is 'images' and
file_name is '/some/path/to/somefile.dat' this will add
'1234/images/somefile.dat' to the Zope filesystem and return
'somefile.dat'.  But in windows if file_name is '
'C:\some\path\to\somefile.dat', the same file will be added to the
Zope filesystem but the entire filename with path will be returned.

I think this is related to the id/title distinction.  In the manager
interface, the linux files are listed as

somefile.dat (somefile.dat)

and the microsoft files are listed as

somefile.dat (C:\some\path\to\somefile.dat)

So it appears that it is the title that is being returned when I want
to the Id.  Any suggestions on how I can modify my script to return
the Id of the newly created File object?

Thanks,
John Hunter