'Create file object.
:param tarfile: Name of TAR file.
:param file: Name of member file.'

def __init__(self, tarfile, file):

    fh = open(tarfile, 'rb')
    while True:
        s = fh.read(512)
        if (len(s) != 512):
            raise IOError('unexpected    end    of    tar    file')
        name = s[:100].decode('utf-8')
        i = name.find('\x00')
        if (i == 0):
            raise IOError('cannot    find    subfile')
        if (i > 0):
            name = name[:i]
        size = int(s[124:135], 8)
        if (file == name):
            break
        fh.seek(((size + 511) & (~ 511)), 1)
    ContainerIO.ContainerIO.__init__(self, fh, fh.tell(), size)
