$ make mpi NAME=prime-gmpmpi
mpicc -g -o prime-gmpmpi prime-gmpmpi.c /usr/local/lib/libgmp.a /usr/local/lib/libsprng.a
cc: /usr/local/lib/libgmp.a: linker input file unused because linking not done
cc: /usr/local/lib/libsprng.a: linker input file unused because linking not done

$ mpirun -np 8 prime-gmpmpi

Do you want to test a number?
 0= done 
 1=yes
 1

Please input the number you wish to check
2305843009213693951
 I heard 1 from 0.
 I heard 1 from 1.
 I heard 1 from 2.
 I heard 1 from 3.
 I heard 1 from 4.
 I heard 1 from 5.
 I heard 1 from 6.
 I heard 1 from 7.
This is a prime.
wall clock time = 19.005737

Do you want to test a number?
 0= done 
 1=yes
 1

Please input the number you wish to check
 2305843009213693953
 I heard 0 from 0.
 I heard 1 from 1.
 I heard 1 from 2.
 I heard 1 from 3.
 I heard 1 from 4.
 I heard 1 from 5.
 I heard 1 from 6.
 I heard 1 from 7.
This is not a prime.
wall clock time = 17.773776

Do you want to test a number?
 0= done 
 1=yes
 0