//// This is a philosopher demo, using process scoping.#include <thread.h>#define MAX_PHILOSOPHERS          5int main(){  mutex *p_fork;  semaphore *sem;  bool fork_v = false;  int lfork, rfork, _nr, _forks = MAX_PHILOSOPHERS, _count;    pthread::set_project( "/tmp/philosophy" );  sem    = new semaphore(attributes::process_shared);  p_fork = new mutex[MAX_PHILOSOPHERS](attributes::process_shared);  if ( (_nr = sem->post()) > MAX_PHILOSOPHERS ) {    sem->trywait();    exit(0);  }  _count = _forks;  _nr -= 1;  lfork = _nr-1 >= 0 ? _nr-1 : _forks-1;  rfork = lfork+1 >= _forks ? 0 : lfork+1;  while(_count-- > 0) {    cout.form("Philosopher %d: looking for %d,%d\n", _nr, lfork, rfork);    while( fork_v == false ) {      if (p_fork[lfork].trylock() == 0) {	if (p_fork[rfork].trylock() == 0)	  fork_v = true;	else	  p_fork[lfork].unlock();      }    }    cout.form("Philosopher %d: using (%d,%d).\n", _nr, lfork, rfork);    sleep(2);    fork_v = false;    cout.form("Philosopher %d: sleeping\n", _nr);    p_fork[lfork].unlock();    p_fork[rfork].unlock();    sleep(2);  }  cout << _nr << " has finished dining." << endl;  sem->trywait();  return 0;}