def get_untracked_fnames(svn):
    fnames = []
    res = subprocess.run(['svn', 'status', svn], capture_output=True)
    output = res.stdout.decode('utf8')
    for line in output.split('\n'):
        if len(line) == 0:
            continue
        modtype = line[0]
        if modtype != '?':
            print('unrecognized line: "{}", ignoring.'.format(line))
            continue
        # new file.  We need to check it in or delete it.
        fname = line[8:]
        fnames.append(fname)
    return fnames