queue.h

在Linux底下用QtDesigner开发的一个进程同步例子。基本思想是设计一个缓冲区（循环队列）

#include <qglobal.h>
struct Circle
{
    int InitX;
    int InitY;
    int InitR;
};

class HQueue{                              //define classes of Cycle Queue
public:
   HQueue(int = 4);
   ~HQueue(){delete []Q;}
   void EnQueue(Circle& item);
   Circle DeQueue();
   Circle GetFront();
   void MakeEmpty(){front = rear = 0;}//tag =0;}                    //get Queue empty
       int IsEmpty() const {return front == rear ;}//&& tag == 0; }   //if Queue is empty
       int IsFull() const {return front == (rear+1)%m;}//&&tag ==1;    //if Queue is full
private:
      // public:
   int rear;                                                  //the signal of Queue tail
   int front;                                                 //the signal of Queue head 
   //int tag;                                                   //the signal of if Queue is full
   Circle *Q;                                                   //a array which store Queue elements
   int m;                                                     //the max size of Queue
};