进程间互斥 Mutex

对于普通的线程间互斥可以使用CreateMutex传建一个匿名的互斥量做互斥,对进程间的互斥就要用到命名互斥量来做互斥了。用到的函数有:
  1.  创建一个命名互斥量使用CreateMutex()方法,只需把lpName参数设置为非NULL,如"my mutex"
 HANDLE WINAPI CreateMutex( 
           __in LPSECURITY_ATTRIBUTES lpMutexAttributes, 
           __in BOOL bInitialOwner, 
           __in LPCTSTR lpName );
2. 打开一个命名互斥量使用OpenMutex()方法,我们也需要对其中的lpName参数指定内容,如"my mutex"
HANDLE WINAPI OpenMutex( 
          __in DWORD dwDesiredAccess, 
          __in BOOL bInheritHandle, 
          __in LPCTSTR lpName ); 
下面给出两段代码,可以同时使用两个process1或process1和process2查看运行效果
进程1的代码:
#include <iostream>
#include <windows.h>
using namespace std;


int main()
{
    /*
    SECURITY_ATTRIBUTES att;
    att.nLength = sizeof(SECURITY_ATTRIBUTES );
    att.lpSecurityDescriptor = NULL;
    att.bInheritHandle = TRUE;
    */

    HANDLE hMutex = CreateMutex(NULL, false, "pmutex");
    if(NULL == hMutex)
    {
        cout<<"create mutex error "<<GetLastError()<<endl;
        return 0;
    }
    else 
    {
        cout<<" create mutex success:"<<hMutex<<endl;
    }

     for(int i = 0;i<10; i++)
    {
        DWORD  d  = WaitForSingleObject(hMutex, INFINITE);
        if(WAIT_OBJECT_0 == d)
        {
            cout<<"begin sleep"<<endl;
            Sleep(2000);
            cout<<"process 1"<<endl;
            if(ReleaseMutex(hMutex)!=0)
            {
                cout<<"reslease ok"<<endl;
            }
            else
            {
                cout<<"reslease failed"<<endl;
            }
        }
        if(WAIT_ABANDONED == d)
        {
            cout<<"WAIT_ABANDONED"<<endl;
        }
        if(WAIT_FAILED ==d)
        {
            cout<<"mutex error"<<endl;
        }
        Sleep(2000);
    }

    CloseHandle(hMutex);
    return 0;
}

  进程2 process2的代码
#include <iostream>
#include <windows.h>
using namespace std;

int main()
{
    HANDLE hMutex = OpenMutex(MUTEX_ALL_ACCESS, false, "pmutex");
    if(NULL == hMutex)
    {
        cout<<"open mutex error "<<GetLastError()<<endl;
        return 0;
    }
    else 
    {
        cout<<"open mutex success:"<<hMutex<<endl;
    }

    for(int i = 0;i<10; i++)
    {
        DWORD  d  = WaitForSingleObject(hMutex, INFINITE);
        if(WAIT_OBJECT_0 == d)
        {
            cout<<"begin sleep"<<endl;
            Sleep(2000);
            cout<<"process 1"<<endl;
            if(ReleaseMutex(hMutex)!=0)
            {
                cout<<"reslease ok"<<endl;
            }
            else
            {
                cout<<"reslease failed"<<endl;
            }
        }
        if(WAIT_ABANDONED == d)
        {
            cout<<"WAIT_ABANDONED"<<endl;
        }
        if(WAIT_FAILED ==d)
        {
            cout<<"mutex error"<<endl;
        }
        Sleep(2000);
    }
    CloseHandle(hMutex);
    return 0;
}

你可能感兴趣的:(进程间互斥 Mutex)