[user@computer dir]$ g++ pp_omp_ex2.cpp -o pp_omp_ex2
[user@computer dir]$ ./pp_omp_ex2 
Doing some stuff
[user@computer dir]$ g++ -fopenmp pp_omp_ex2.cpp -o pp_omp_ex2
[user@computer dir]$ ./pp_omp_ex2 
Doing some stuffDoing some stuff

[user@computer dir]$ export OMP_NUM_THREADS=6
[user@computer dir]$ ./pp_omp_ex2 
Doing some stuffDoing some stuffDoing some stuff
Doing some stuff
Doing some stuff
Doing some stuff


[user@computer dir]$