# Win32多線程程序設計-同步控制
```
#include "pch.h"
//#include <iostream>
#include "windows.h"
#include "stdio.h"
bool flag;
CRITICAL_SECTION cs;
DWORD WINAPI Thread1_Proc(PVOID pvParam)
{
while (1)
{
do { ; } while (1 == flag);
EnterCriticalSection(&cs);
printf("Hello,");
LeaveCriticalSection(&cs);
flag = 1;
Sleep(50);
}
}
DWORD WINAPI Thread2_Proc(PVOID pvParam)
{
while (1)
{
do { ; } while (0 == flag);
EnterCriticalSection(&cs);
printf("World!\n");
LeaveCriticalSection(&cs);
flag = 0;
Sleep(50);
}
}
int main(int argc, char* argv[])
{
DWORD nID;
InitializeCriticalSection(&cs);
CreateThread(NULL, 0, Thread1_Proc, NULL, 0, NULL);
CreateThread(NULL, 0, Thread2_Proc, NULL, 0, NULL);
while (1)
{
;
}
DeleteCriticalSection(&cs);
return 0;
}
```
//改進了一下！：
```
#include "pch.h"
//#include <iostream>
#include "windows.h"
#include "stdio.h"
char flagc = '.';// | ';// .';
bool flag;
CRITICAL_SECTION cs;
DWORD WINAPI Thread1_Proc(PVOID pvParam)
{
while (1)
{
// while (1 == flag);
while ('.' == flagc) { Sleep(1);}
EnterCriticalSection(&cs);
printf("[");
for (int i = 0; i < 19159; ++i) {
printf("."); //printf("[%d]" , i);
}//[i%d]", i); }
printf("]\r\n");
LeaveCriticalSection(&cs);
flagc = '.';// flag = 1;
Sleep(50);
}
}
DWORD WINAPI Thread2_Proc(PVOID pvParam)
{
while (1)
{
while ('|' == flag) { Sleep(2);}//while (0 == flag) { Sleep(2);}
EnterCriticalSection(&cs);
printf("<");
for(int j=0;j<9149;++j) {printf("|%d|",j);}
printf(">\r\n");
LeaveCriticalSection(&cs);
flagc = '|';// flag = 0;
Sleep(50);
}
}
int main(int argc, char* argv[])
{
DWORD nID;
InitializeCriticalSection(&cs);
CreateThread(NULL, 0, Thread1_Proc, NULL, 0, NULL);
CreateThread(NULL, 0, Thread2_Proc, NULL, 0, NULL);
while (1)
{
;
}
DeleteCriticalSection(&cs);
return 0;
}//main()
```
