def METHOD_NAME(fileid, rootdir=None, #*,
               normalize=False,
               strictpathsep=None,
               _pathsep=PATH_SEP,
               **kwargs
               ):
    """Return a pathsep-separated file ID ("./"-prefixed) for the given value.
    The file ID may be absolute.  If so and "rootdir" is
    provided then make the file ID relative.  If absolute but "rootdir"
    is not provided then leave it absolute.
    """
    if not fileid or fileid == '.':
        return fileid
    # We default to "/" (forward slash) as the final path sep, since
    # that gives us a consistent, cross-platform result.  (Windows does
    # actually support "/" as a path separator.)  Most notably, node IDs
    # from pytest use "/" as the path separator by default.
    _fileid = fileid.replace(_pathsep, '/')
    relpath = _resolve_relpath(_fileid, rootdir,
                               _pathsep=_pathsep,
                               **kwargs
                               )
    if relpath:  # Note that we treat "" here as an absolute path.
        _fileid = './' + relpath
    if normalize:
        if strictpathsep:
            raise ValueError(
                    'cannot normalize *and* keep strict path separator')
        _fileid = _str_to_lower(_fileid)
    elif strictpathsep:
        # We do not use _normcase since we want to preserve capitalization.
        _fileid = _fileid.replace('/', _pathsep)
    return _fileid