怎么向缓冲区输入数据，等到一定数量再输出

怎么向缓冲区输入数据，等到缓冲区一定数量再输出。不要用writeconsoleoutputcharactera（），因为我要输出特殊字符，或者是可以有什么其他的办法防止屏幕闪烁，一个小游戏，有相关函数的话可以告诉一下吗，谢谢了。

仅供参考：

#include <conio.h>
#include <windows.h>

void ConPrintAt(int x, int y, char *CharBuffer, int len)
{
   DWORD count;
   COORD coord = {x, y};
   HANDLE hStdOut = GetStdHandle(STD_OUTPUT_HANDLE);
   SetConsoleCursorPosition(hStdOut, coord);
   WriteConsole(hStdOut, CharBuffer, len, &count, NULL);
}
void HideTheCursor()
{
   CONSOLE_CURSOR_INFO cciCursor;
   HANDLE hStdOut = GetStdHandle(STD_OUTPUT_HANDLE);

   if(GetConsoleCursorInfo(hStdOut, &cciCursor))
   {
      cciCursor.bVisible = FALSE;
      SetConsoleCursorInfo(hStdOut, &cciCursor);
   }
}

void ShowTheCursor()
{
   CONSOLE_CURSOR_INFO cciCursor;
   HANDLE hStdOut = GetStdHandle(STD_OUTPUT_HANDLE);

   if(GetConsoleCursorInfo(hStdOut, &cciCursor))
   {
      cciCursor.bVisible = TRUE;
      SetConsoleCursorInfo(hStdOut, &cciCursor);
   }
}
void GetWH(int *w,int *h) {
    HANDLE hStdOut = GetStdHandle(STD_OUTPUT_HANDLE);
    CONSOLE_SCREEN_BUFFER_INFO csbi;
    if (GetConsoleScreenBufferInfo(hStdOut, &csbi)) {
        *w=csbi.srWindow.Right;
        *h=csbi.srWindow.Bottom;
    } else {
        *w=80;
        *h=25;
    }
}
void ClearConsole()
{
   //Get the handle to the current output buffer...
   HANDLE hStdOut = GetStdHandle(STD_OUTPUT_HANDLE);
   //This is used to reset the carat/cursor to the top left.
   COORD coord = {0, 0};
   //A return value... indicating how many chars were written
   //   not used but we need to capture this since it will be
   //   written anyway (passing NULL causes an access violation).
   DWORD count;
   //This is a structure containing all of the console info
   // it is used here to find the size of the console.
   CONSOLE_SCREEN_BUFFER_INFO csbi;
   //Here we will set the current color
   if(GetConsoleScreenBufferInfo(hStdOut, &csbi))
   {
      //This fills the buffer with a given character (in this case 32=space).
      FillConsoleOutputCharacter(hStdOut, (TCHAR) 32, csbi.dwSize.X * csbi.dwSize.Y, coord, &count);
      FillConsoleOutputAttribute(hStdOut, csbi.wAttributes, csbi.dwSize.X * csbi.dwSize.Y, coord, &count);
      //This will set our cursor position for the next print statement.
      SetConsoleCursorPosition(hStdOut, coord);
   }
}

int main() {
    unsigned short k;
    int x,y,w,h;
    char d;

    SetConsoleOutputCP(437);
    ClearConsole();
    GetWH(&w,&h);
    x=w/2;y=h/2;
    HideTheCursor();
    ConPrintAt(x,y,"O",1);
    d='o';
    while (1) {
        Sleep(50);
        if (kbhit()) {
            k=getch();
            if (27==k) break;//按Esc键退出
            if (0==k||0xe0==k) k|=getch()<<8;//非字符键
            switch (k) {
                case 0x48e0:case 0x04800://上
                    d='u';
                    if (y>0) {
                        ConPrintAt(x,y," ",1);
                        y--;
                        ConPrintAt(x,y,"O",1);
                    }
                break;
                case 0x50e0:case 0x05000://下
                    d='d';
                    if (y<h) {
                        ConPrintAt(x,y," ",1);
                        y++;
                        ConPrintAt(x,y,"O",1);
                    }
                break;
                case 0x4be0:case 0x04b00://左
                    d='l';
                    if (x>0) {
                        ConPrintAt(x,y," ",1);
                        x--;
                        ConPrintAt(x,y,"O",1);
                    }
                break;
                case 0x4de0:case 0x04d00://右
                    d='r';
                    if (x<w-1) {
                        ConPrintAt(x,y," ",1);
                        x++;
                        ConPrintAt(x,y,"O",1);
                    }
                break;
            }
//          cprintf("%04x pressed.\r\n",k);
        } else {
            switch (d) {
                case 'u':
                    if (y>0) {
                        ConPrintAt(x,y," ",1);
                        y--;
                        ConPrintAt(x,y,"O",1);
                    }
                break;
                case 'd':
                    if (y<h) {
                        ConPrintAt(x,y," ",1);
                        y++;
                        ConPrintAt(x,y,"O",1);
                    }
                break;
                case 'l':
                    if (x>0) {
                        ConPrintAt(x,y," ",1);
                        x--;
                        ConPrintAt(x,y,"O",1);
                    }
                break;
                case 'r':
                    if (x<w-1) {
                        ConPrintAt(x,y," ",1);
                        x++;
                        ConPrintAt(x,y,"O",1);
                    }
                break;
            }
        }
    }
    ClearConsole();
    ShowTheCursor();
    return 0;
}

另外还可以参考：
console屏幕处理例子程序。终端窗口屏幕处理相关API使用例子。来自MSVC20\SAMPLES\win32\console\ http://download.csdn.net/detail/zhao4zhong1/3461309

你的缓冲区输出的目的地，是指控制台（console）吗？
如果是控制台（stdout）或者其他文件流的话，可以用setvbuf为重新设置缓冲区大小。不要调用fflush冲刷文件流，输出内容里面也不能包含'\n'，std::endl。