When a solver starts up, it displays a brief identification string such as MINOS 5.5 or CPLEX 12.4 . Output that occurs before this string can be assumed to come from AMPL, while output after is the solver’s.
When a solver concludes its run, it returns a brief summary of the results, such as
optimal solution; objective 903202.0326
399 iterations (244 in phase I)
Output prior to this summary can be assumed to be caused by the solver, while output after is from AMPL again.