Reference

The fold simlib/ refered to yusufRahmatullah

And I had modified its source code of simlib.c to fit my needs:

line 557        if (variable < 0)
                {				/* Report summary statistics in transfer. */
                    ivar = -variable;
                    area[ivar] += (sim_time - tlvc[ivar]) * preval[ivar];
                    tlvc[ivar] = sim_time;
                    transfer[1] = area[ivar] / (sim_time - treset);
                    transfer[2] = max[ivar];
                    transfer[3] = min[ivar];
+                   transfer[4] = area[ivar];
                    return transfer[1];
line 567        }

Usage

for elevator simulation by simlib

$ cd examples/elevator-system-model/
$ make run

Above command will generate the esm.out and debug.log, which is the report of simulation and debug information respectively.

for elevator simulation by gpss world

1. Firstly, you mush install the examples/gpss-elevator-simulation/gpss_world_student_setup.msi in your windows machine.
2. Secondly, use the software installed above to open the examples/gpss-elevator-simulation/elevator.gps file.
3. Lastly, it's your time to start simulation using this old and fancy gpss-world software. Maybe gpss world tutorial and gpss world user reference can help you.