使用互斥对象进行线程同步

 

#include <windows.h>
#include <stdio.h>

#define NUM_THREADS 4

DWORD dwCounter = 0;
HANDLE hMutex;

void UseMutex(void);
DWORD WINAPI MutexThread(LPVOID lpParam);

int main(void){
    UseMutex();
}

void UseMutex(void){
    INT i;
    HANDLE hThread;
    hMutex = CreateMutex(NULL,FALSE,NULL);
    if(hMutex == NULL){
        printf("Create mutex error.(%d)\n",GetLastError());
        return;
    }
    for(i=0;i<NUM_THREADS;i++){
        hThread = CreateThread(NULL,0,MutexThread,NULL,0,NULL);
        if(hThread == NULL){
            printf("Create thread error.(%d)\n",GetLastError());
            return;
        }
    }
    Sleep(1000);
}

DWORD WINAPI MutexThread(LPVOID lpParam){
    DWORD dwMutexResult;
    dwMutexResult = WaitForSingleObject(hMutex,INFINITE);
    switch(dwMutexResult){
    case WAIT_OBJECT_0:
        Sleep(rand()%100);
        printf("counter:%d\n",dwCounter);
        dwCounter++;
        if(!ReleaseMutex(hMutex)){
            printf("Release Mutex error.(%d)\n",GetLastError());
        }
        break;
    default:
        printf("Wait error.(%d)\n",GetLastError());
        ExitProcess(0);
    }
    return 1;
}