  We consider a quasi two-dimensional superconductor with line nodes in an
in-plane magnetic field, and compute the dependence of the specific heat, $C$,
and the in-plane heat conductivity, $\kappa$, on the angle between the field
and the nodal direction in the vortex state. We use a variation of the
microscopic Brandt-Pesch-Tewordt method that accounts for the scattering of
quasiparticles off vortices, and analyze the signature of the nodes in $C$ and
$\kappa$. At low to moderate fields the specific heat anisotropy changes sign
with increasing temperature. Comparison with measurements of $C$ and $\kappa$
in CeCoIn$_5$ resolves the contradiction between the two in favor of the
$d_{x^2-y^2}$ gap.
