Overloaded >>

I need to use the overloaded >> this way

Code:

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// while "std::cin >> process" is succesfull
while (std::cin >> process && !(ph.isFull())) {
    // do something
}

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Code:

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std::istream &operator>>(std::istream &stream, PCB &pcb)
  char* temp = new char[MAX_HOOK_LEN];    // Temporary holder for process info

  stream >> pcb.pid;
  if (pcb.pid == -1) {  // '-1' indicates end of input
    return ????  //what to return
  }
  stream >> pcb.arrival_time;
  stream >> pcb.last_cpu_burst;
  stream >> pcb.test_cpu_burst;
  stream >> pcb.priority;
  stream >> pcb.state_status;
  if (stream.getline(temp, MAX_HOOK_LEN, '\n')){
    pcb.hook = temp;
  }
 
  return stream;
}

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What you return is a reference to an istream (naturally), before you return you set the failbit to indicate that you could not read a new record, and eofbit to indicate that you cannot read another record because you have read them all.

Code:

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std::istream &operator>>(std::istream &stream, PCB &pcb)
    PCB temp;

    stream >> temp.pid;
    if(temp.pid == -1) {
        stream.setstate(std::ios_base::failbit | std::ios_base::eofbit);
        return stream;
    }
    stream >> temp.arrival_time;
    stream >> temp.last_cpu_burst;
    stream >> temp.test_cpu_burst;
    stream >> temp.priority;
    stream >> temp.state_status;
    getline(stream,temp.hook);
    if(stream) pcb.swap(temp);
    return stream;
}

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This assumes that PCB uses a std::string for it's hook, otherwise you have a memory leak in your previous code. This also obeys the convention that I always use that all >> operations leave thier targets unchanged. swap() is a new member that makes this and many other things much easier.

hhmmm, interesting makeover you did there
thanks for the new knowledge and insight