#define __THREADS_MAIN#include <thread.h>#include <threads/signal_num.h>#include <iostream>#include <string>extern "C" {#  include <sys/wait.h>#  include <unistd.h>};using namespace std;using namespace cpp_threads;Cond  t_control;Mutex t_link;string s;class producer : public Pthread {public:  producer() { };  ~producer() { };  int thread(void *)    {      char *buf = new char[80];      cout << "Enter text for consumer: ";      cout.flush();      cin.getline(buf,80);      cout << "got '" << buf << "'\n";      t_link.lock();      s = buf;      t_control.signal();      t_link.unLock();      delete buf;      return 0;    }};class consumer : public Pthread {public:  consumer() { };  ~consumer() { };  int thread(void *)    {      int r;      t_link.lock();      t_control.wait(t_link);      cout << "Consumed: '" << s << "'\n";      r = s.length();      t_link.unLock();      return r;    }};int main(){  Pthread* p1, *p2;  p1 = new consumer;  p2 = new producer;    p1->run();  p2->run();  p1->join();  cout << "return value " << p1->retcode() << endl;  delete p2;  delete p1;}