承接上一篇:https://blog.youkuaiyun.com/uVarAndMethod/article/details/90360838
1、内核对象:
进程、线程、文件、文件映射、事件、互斥体等等
2、事件内核对象的创建
HANDLE g_hEvent = CreateEvent(NULL, TRUE, FALSE, "XYZ");
HANDLE g_hMutex = CreateMutex(NULL,FALSE, "XYZ");
3、事件内核对象的获取
HANDLE OpenEvent(
DWORD dwDesiredAccess, // access
BOOL bInheritHandle, // inheritance option
LPCTSTR lpName // object name
);
HANDLE g_hEvent = OpenEvent(EVENT_ALL_ACCESS, FALSE, "XYZ");
HANDLE g_hMutex = OpenMutex(MUTEX_ALL_ACCESS,FALSE, "XYZ");
4、内核对象的销毁
BOOL CloseHandle(HANDLE hobj);
(1)、当没有其他程序引用时,系统会销毁内核对象(使用数量).
(2)、内核对象的生命周期,可能比创建它的对象要长.
5、内核对象的生命周期
eg:CloseHandle()/进程结束
进程一:
HANDLE g_hEvent = CreateEvent(NULL, TRUE, FALSE, "XYZ");
SetEvent(g_hEvent);
进程二:
HANDLE g_hEvent = OpenEvent(EVENT_ALL_ACCESS, FALSE, "XYZ");
WaitForSingleObject(g_hEvent, INFINITE);
eg:内核对象的生命周期
进程一:
HANDLE g_hEvent = CreateEvent(NULL, TRUE, FALSE, "XYZ");
SetEvent(g_hEvent);
进程二:
HANDLE g_hEvent = OpenEvent(EVENT_ALL_ACCESS, FALSE, "XYZ");
WaitForSingleObject(g_hEvent, INFINITE);
///
1、事件对象的创建
HANDLE CreateEvent(
LPSECURITY_ATTRIBUTES lpEventAttributes, // 安全属性 NULL时为系统默认
BOOL bManualReset, // TRUE 通过调用ResetEvent将事件对象标记为未通知
BOOL bInitialState, // TRUE 已通知状态 FALSE未通知状态
LPCTSTR lpName // 对象名称 以NULL结尾的字符串
);
2、事件对象的控制
BOOL SetEvent(HANDLE hEvent); //将对象设置为已通知
3、关闭时间对象句柄
//关闭句柄
CloseHandle();
4、线程控制实验:只读形式的线程控制
HANDLE g_hEvent;
HWND hEdit1;
HWND hEdit2;
HWND hEdit3;
HWND hEdit4;
HANDLE hThread1;
HANDLE hThread2;
HANDLE hThread3;
HANDLE hThread4;
DWORD WINAPI ThreadProc1(LPVOID lpParameter)
{
//创建事件
//默认安全属性 手动设置未通知状态(TRUE) 初始状态未通知 没有名字
g_hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
HANDLE hThread[3];
//创建3个线程
hThread[0] = ::CreateThread(NULL, 0, ThreadProc2, NULL, 0, NULL);
hThread[1] = ::CreateThread(NULL, 0, ThreadProc3, NULL, 0, NULL);
hThread[2] = ::CreateThread(NULL, 0, ThreadProc4, NULL, 0, NULL);
//设置文本框的值
SetWindowText(hEdit1,"1000");
//设置事件为已通知
SetEvent(g_hEvent);
//等待线程结束 销毁内核对象
WaitForMultipleObjects(3, hThread, TRUE, INFINITE);
CloseHandle(hThread[0]);
CloseHandle(hThread[1]);
CloseHandle(hThread[2]);
CloseHandle(g_hEvent);
return 0;
}
DWORD WINAPI ThreadProc2(LPVOID lpParameter)
{
TCHAR szBuffer[10] = {0};
//当事件变成已通知时
WaitForSingleObject(g_hEvent, INFINITE);
//读取内容
GetWindowText(hEdit1,szBuffer,10);
SetWindowText(hEdit2,szBuffer);
return 0;
}
DWORD WINAPI ThreadProc3(LPVOID lpParameter)
{
TCHAR szBuffer[10] = {0};
//当事件变成已通知时
WaitForSingleObject(g_hEvent, INFINITE);
//读取内容
GetWindowText(hEdit1,szBuffer,10);
SetWindowText(hEdit3,szBuffer);
return 0;
}
DWORD WINAPI ThreadProc4(LPVOID lpParameter)
{
TCHAR szBuffer[10] = {0};
//当事件变成已通知时
WaitForSingleObject(g_hEvent, INFINITE);
//读取内容
GetWindowText(hEdit1,szBuffer,10);
SetWindowText(hEdit4,szBuffer);
return 0;
}
创建信号量
HANDLE CreateSemaphore(
LPSECURITY_ATTRIBUTES lpSemaphoreAttributes,
LONG lInitialCount,
LONG lMaximumCount,
LPCTSTR lpName
);
函数说明:
第一个参数表示安全控制,一般直接传入NULL。
第二个参数表示初始资源数量。0时不发送信号
第三个参数表示最大并发数量。lInitialCount<=lMaximumCount
第四个参数表示信号量的名称,传入NULL表示匿名信号量。
打开信号量
HANDLE OpenSemaphore(
DWORD dwDesiredAccess,
BOOL bInheritHandle,
LPCTSTR lpName
);
函数说明:
第一个参数表示访问权限,对一般传入SEMAPHORE_ALL_ACCESS。详细解释可以查看MSDN文档。
第二个参数表示信号量句柄继承性,一般传入FALSE即可。
第三个参数表示名称,不同进程中的各线程可以通过名称来确保它们访问同一个信号量。
递增信号量的当前资源计数
BOOL ReleaseSemaphore(
HANDLE hSemaphore,
LONG lReleaseCount,
LPLONG lpPreviousCount
);
函数说明:
第一个参数是信号量的句柄。
第二个参数表示增加个数,必须大于0且不超过最大资源数量。
第三个参数返回当前资源数量的原始值,设为NULL表示不需要传出。
注:没有一个函数可以用来查询信标的当前资源数量的值
信号量的清理与销毁
CloseHandle()
通过信号量控制对资源的访问:
见MSDN
eg:
信号量应用
#include "stdafx.h"
#include "resource.h"
HANDLE hSemaphore;
HANDLE hThread[3];
HWND hEditSet;
HWND hEdit1;
HWND hEdit2;
HWND hEdit3;
DWORD WINAPI ThreadProc1(LPVOID lpParameter)
{
TCHAR szBuffer[10];
DWORD dwTimmer=0;
WaitForSingleObject(hSemaphore, INFINITE);
while(dwTimmer<100)
{
Sleep(100);
memset(szBuffer,0,10);
GetWindowText(hEdit1,szBuffer,10);
sscanf( szBuffer, "%d", &dwTimmer );
dwTimmer++;
memset(szBuffer,0,10);
sprintf(szBuffer,"%d",dwTimmer);
SetWindowText(hEdit1,szBuffer);
}
ReleaseSemaphore(hSemaphore, 1, NULL);
return 0;
}
DWORD WINAPI ThreadProc2(LPVOID lpParameter)
{
TCHAR szBuffer[10];
DWORD dwTimmer=0;
WaitForSingleObject(hSemaphore, INFINITE);
while(dwTimmer<100)
{
Sleep(100);
memset(szBuffer,0,10);
GetWindowText(hEdit2,szBuffer,10);
sscanf( szBuffer, "%d", &dwTimmer );
dwTimmer++;
memset(szBuffer,0,10);
sprintf(szBuffer,"%d",dwTimmer);
SetWindowText(hEdit2,szBuffer);
}
ReleaseSemaphore(hSemaphore, 1, NULL);
return 0;
}
DWORD WINAPI ThreadProc3(LPVOID lpParameter)
{
TCHAR szBuffer[10];
DWORD dwTimmer=0;
WaitForSingleObject(hSemaphore, INFINITE);
while(dwTimmer<100)
{
Sleep(100);
memset(szBuffer,0,10);
GetWindowText(hEdit3,szBuffer,10);
sscanf( szBuffer, "%d", &dwTimmer );
dwTimmer++;
memset(szBuffer,0,10);
sprintf(szBuffer,"%d",dwTimmer);
SetWindowText(hEdit3,szBuffer);
}
ReleaseSemaphore(hSemaphore, 1, NULL);
return 0;
}
DWORD WINAPI ThreadBegin(LPVOID lpParameter)
{
TCHAR szBuffer[10];
DWORD dwMoney=0;
hSemaphore = CreateSemaphore(NULL,0,3,NULL);
hThread[0] = ::CreateThread(NULL, 0, ThreadProc1,NULL, 0, NULL);
hThread[1] = ::CreateThread(NULL, 0, ThreadProc2,NULL, 0, NULL);
hThread[2] = ::CreateThread(NULL, 0, ThreadProc3,NULL, 0, NULL);
//开始准备红包
while(dwMoney<1000)
{
memset(szBuffer,0,10);
GetWindowText(hEditSet,szBuffer,10);
sscanf( szBuffer, "%d", &dwMoney );
dwMoney++;
memset(szBuffer,0,10);
sprintf(szBuffer,"%d",dwMoney);
SetWindowText(hEditSet,szBuffer);
}
ReleaseSemaphore(hSemaphore, 2, NULL);
::WaitForMultipleObjects(3, hThread,TRUE,INFINITE);
::CloseHandle(hSemaphore);
return 0;
}
BOOL CALLBACK MainDlgProc(HWND hDlg,UINT uMsg,WPARAM wParam,LPARAM lParam)
{
BOOL bRet = FALSE;
switch(uMsg)
{
case WM_CLOSE:
{
EndDialog(hDlg,0);
break;
}
case WM_INITDIALOG:
{
hEditSet = GetDlgItem(hDlg,IDC_EDIT_SET);
hEdit1 = GetDlgItem(hDlg,IDC_EDIT_1);
hEdit2 = GetDlgItem(hDlg,IDC_EDIT_2);
hEdit3 = GetDlgItem(hDlg,IDC_EDIT_3);
SetWindowText(hEditSet,"0");
SetWindowText(hEdit1,"0");
SetWindowText(hEdit2,"0");
SetWindowText(hEdit3,"0");
break;
}
case WM_COMMAND:
switch (LOWORD (wParam))
{
case IDC_BUTTON_BEGIN:
{
CreateThread(NULL, 0, ThreadBegin,NULL, 0, NULL);
return TRUE;
}
}
break ;
}
return bRet;
}
int APIENTRY WinMain(HINSTANCE hInstance,
HINSTANCE hPrevInstance,
LPSTR lpCmdLine,
int nCmdShow)
{
// TODO: Place code here.
DialogBox(hInstance,MAKEINTRESOURCE(IDD_DIALOG_MAIN),NULL,MainDlgProc);
return 0;
}