一个很简单的多线程程序，主要用于了解临界区的使用

#include
#include
#include

#pragma comment(lib,"libcmt.lib")

const int NLOOP = 100;

int counter = 0;

void doit(void*);

CRITICAL_SECTION beswap ;

int main()
{

 HANDLE pnt[2];

 InitializeCriticalSection(&beswap);

 pnt[0] = (HANDLE)_beginthread(doit,0,NULL);
 pnt[1] = (HANDLE)_beginthread(doit,0,NULL);

 WaitForMultipleObjects( 2, pnt, TRUE, 1000L);

 DeleteCriticalSection(&beswap);
 
 return 0;
}

void doit(void*)
{
 printf("go...\n");

 int i, val = 0;

 for(i = 0; i < NLOOP; ++i)
 {
  EnterCriticalSection(&beswap);

  val = counter;
  printf("%d\n",val+1);
  counter = val + 1;

  LeaveCriticalSection(&beswap);
 }

 printf("end...\n");

 return ;
}