  We present an improved version of GENXICC, which is a generator for hadronic
production of the doubly heavy baryons $\Xi_{cc}$, $\Xi_{bc}$ and $\Xi_{bb}$
and has been raised by C.H. Chang, J.X. Wang and X.G. Wu [Comput. Phys. Commun.
177 (2007) 467; Comput. Phys. Commun. 181 (2010) 1144]. In comparison with the
previous GENXICC versions, we update the program in order to generate the
unweighted baryon events more effectively under various simulation
environments, whose distributions are now generated according to the
probability proportional to the integrand. One Les Houches Event (LHE) common
block has been added to produce a standard LHE data file that contains useful
information of the doubly heavy baryon and its accompanying partons. Such LHE
data can be conveniently imported into PYTHIA to do further hadronization and
decay simulation, especially, the color-flow problem can be solved with
PYTHIA8.0.
