  We measure the cross section and the difference in rapidities between photons
and charged leptons for inclusive W -> lnu+gamma production in egamma and
mugamma final states. Using data corresponding to an integrated luminosity of
4.2 fb-1 collected with the D0 detector at the Fermilab Tevatron Collider, the
cross section multiplied by the branching fraction for the process ppbar ->
Wgamma+X -> lnugamma+X, measured to be 15.8 +/- 0.8 (stat.) +/- 1.2 (syst.) pb,
and the distribution of the charge-signed photon-lepton rapidity difference are
found to be in agreement with the standard model. These results provide the
most stringent limits on anomalous WWgamma couplings for data from hadron
colliders: -0.4 < Delta kappa_gamma < 0.4 and -0.08 < lambda_gamma < 0.07 at
the 95% C.L.
