XilVitisNetP4DpiCreateEnv() produces a return
value, the data type of which is chandle. This data type is used
by SystemVerilog to hold pointers to memory in the DPI library. In the case of the
example designs, the memory being pointed to is a data structure needed for successful
initialization of the control plane drivers by the testbench. The testbench must call
the XilVitisNetP4DpiCreateEnv() function once for each
VitisNetP4 instance, and store the return values in variables.