$ mpiexec -n 4 ./cpi
Process 1 on jesc-HP-Z800-Workstation
Process 2 on jesc-HP-Z800-Workstation
Process 3 on jesc-HP-Z800-Workstation
Process 0 on jesc-HP-Z800-Workstation
pi is approximately 3.1416009869231249, Error is 0.0000083333333318
wall clock time = 0.000282