  1FGL J1018.6-5856 is a high mass gamma-ray binary containing a compact object
orbiting around a massive star with a period of 16.544 d. If the compact object
is a pulsar, non-thermal emissions are likely produced by electrons accelerated
at the termination shock, and may also originate from the magnetosphere and the
un-shocked wind of the pulsar. In this paper, we investigate the non-thermal
emissions from the wind and the shock with different viewing geometries and
study the multi-wavelength emissions from 1FGL J1018.6-5856. We present the
analysis results of the \textit{Fermi}/LAT using nearly 10 years of data. The
phase-resolved spectra indicate that the GeV emissions comprise a rather steady
component that does not vary with orbital motion and a modulated component that
shows flux maximum around inferior conjunction. The keV/TeV light curves of
1FGL J1018.6-5856 also exhibit a sharp peak around inferior conjunction, which
are attributed to the boosted emission from the shock, while the broad
sinusoidal modulations could be originating from the deflected shock tail at a
larger distance. The modulations of GeV flux are likely caused by the boosted
synchrotron emission from the shock and the IC emission from the un-shocked
pulsar wind, while the steady component comes from the outer gap of the pulsar
magnetosphere. Finally, we discuss the similarities and differences of 1FGL
J1018.6-5856 with other binaries, like LS 5039.
