1.在main函数中分别引入线程t1 和线程 t2

    一个线程用来刷新界面，一个线程用来改变方向

2.刷新界面函数，无限次刷新

3. 也是无限循环while(1) 定义key 从键盘获取输入方向，赋值给dir;

4.在初始化函数中确定蛇向有行走为方向

5.从改变方向的函数changeDir()函数中获取dir的方向，在增加节点函数addNode()中，用switch函数实现蛇方向的改变

代码演示：

#include <curses.h>
#include <stdlib.h>
#include <unistd.h>
#include <pthread.h>

#define UP   1
#define DOWN 2
#define LEFT 3
#define RIGHT   4

void initNcurses()
{
        initscr();
        keypad(stdscr,1);
        noecho();
}

struct Snake
{
        int hang;
        int lie;
        struct Snake *next;

};

struct Snake *head = NULL;
struct Snake *tail = NULL;
int key;
int dir;

int hasSnakeNode(int i,int j){       // da yin she shen ti
        struct Snake *p;
        p = head;  //ding tou 

        while(p != NULL){
                if(p -> hang == i && p ->lie == j){
                        return 1;
                } 
                p = p ->next;
        }
        return 0;
}

void gamePic()
{
        int hang;
        int lie;

        move(0,0);

        for(hang = 0;hang<20;hang++){
                if(hang==0)
                {
                        for(lie=0;lie<20;lie++)
 {
                                printw("--");
                        }
                        printw("\n");
                }
                if(hang>= 0 || hang <=18)
                {
                        for(lie = 0;lie<=20;lie++){
                                if(lie == 0 || lie == 20){
                                        printw("|");
                                }else if(hasSnakeNode(hang,lie))
                                {
                                        printw("[]");
                                }else
                                    {
                                                printw("  ");
                                    }
                        }
                        printw("\n");
                }
                if(hang == 19)
                {
                        for(lie=0;lie<20;lie++){
                                printw("--");
                        }
                        printw("\n");
                        printw("by caoshupei,key= %d\n",key);
                }
        }
}

void addNode()
{
        struct Snake *new = (struct Snake *)malloc(sizeof(struct Snake));
        new -> next =NULL;
        switch(dir){
                case UP:
                        new -> hang = tail -> hang-1;
                        new -> lie = tail -> lie;
                        break;
                case DOWN:
                        new -> hang = tail -> hang+1;
                        new -> lie = tail ->lie;
 break;
                case LEFT:
                        new -> hang = tail -> hang;
                        new ->lie = tail -> lie-1;
                        break;
                case RIGHT:
                        new -> hang = tail -> hang;
                        new -> lie = tail -> lie+1;
                        break;


        }

        tail -> next = new;
        tail = new;
}

void deleteNode()
{
        struct Snake *p;
        p = head;
        head = head ->next;

        free(p);    // fang zhi zao cheng hen duo kong yu de jie dian
}

void  initSnakebody()
{
        struct Snake *p;

        dir = RIGHT;
                                                //di yi ci yun xing shi bu hui zou
        while(head != NULL)                  //yi kai shi deng yu kong
        {                                  //zhuang qiao la jiu shi bu wei kong 
                p = head;
                head = head -> next;
                free(p);                   //shi fang nei cun
        }

        head = (struct Snake*)malloc(sizeof(struct Snake));
        head -> hang = 1;                   // gu ding chu shi weizhi 
        head -> lie = 1;
        head -> next = NULL;               // tou de xie yi ge wei kong

        tail = head;                       // wei ba bian cheng tou
        addNode();                         // zeng jia jie dian
        addNode();
        addNode();
}

void moveSnake()
{
        struct Snake *p;
struct Snake *new;

        addNode();
        deleteNode();
        if(tail -> hang == 0|| tail ->lie == 0|| tail->hang == 20 ||
                tail->lie ==20)
        {
                initSnakebody();
        }
}

void *refreshjiemian()
{
        while(1){
                        moveSnake();
                        gamePic();
                        refresh();
                        usleep(100000);
        }
}

void *changeDir()
{
        while(1){
                key = getch();
                switch(key){
                        case KEY_DOWN:
                                dir = DOWN;
                                break;
                        case KEY_UP:
                                dir = UP;
                                break;
                        case KEY_LEFT:
                                dir = LEFT;
                                break;
                        case KEY_RIGHT:
                                dir = RIGHT;
                                break;
                }
        }
}

int main()
{
        pthread_t t1;
        pthread_t t2;
        initNcurses();
        initSnakebody();
        gamePic();

        pthread_create(&t1,NULL,refreshjiemian,NULL);
        sleep(1);
        pthread_create(&t2,NULL,changeDir,NULL);
        while(1);
        getch();
        endwin();
        return 0;
}