  We present the complete NLO QCD analysis of the photon structure functions
$F_2^\gamma(x,Q^2)$ and $F_L^\gamma(x,Q^2)$ for a real photon target. In
particular we study the heavy flavor content of the structure functions which
is due to two different production mechanisms, namely collisions of a virtual
photon with a real photon, and with a parton. We observe that the charm
contributions are noticeable for $F_2^\gamma(x,Q^2)$ as well as
$F_L^\gamma(x,Q^2)$ in the x-region studied.
