Print the number of cores available to the current process.
If the OMP_NUM_THREADS or OMP_THREAD_LIMIT environment variables are set, then
they will determine the minimum and maximum returned value respectively.

Usage: nproc [OPTIONS]...

Options:
      --all         print the number of cores available to the system
      --ignore <N>  ignore up to N cores [default: 0]
  -h, --help        Print help
  -V, --version     Print version