Worker線程使用訊息迴圈

/* * Worker.cpp * * Sample code for "Multithreading Applications in Win32" * This is from Chapter 14, Listing 14-3 * * Demonstrate using worker threads that have * their own message queue but no window. */ #define WIN32_LEAN_AND_MEAN#include <stdio.h>#include <stdlib.h>#include <windows.h>#include <process.h>#include <string.h>#include "MtVerify.h"unsigned WINAPI ThreadFunc(void* p);HANDLE ghEvent;#define WM_JOB_PRINT_AS_IS          WM_APP + 0x0001#define WM_JOB_PRINT_REVERSE        WM_APP + 0x0002#define WM_JOB_PRINT_LOWER          WM_APP + 0x0003#define WM_LEIWEIWM_APP + 0x0004int main(VOID) {     HANDLE hThread;    unsigned tid;    // Give the new thread something to talk    // to us with.//建立手動事件    ghEvent = CreateEvent(NULL, TRUE, FALSE, NULL);unsigned CurrentId = GetCurrentThreadId();UNREFERENCED_PARAMETER(CurrentId);    hThread = (HANDLE)_beginthreadex(NULL,                      0,                      ThreadFunc,                      0,                      0,                      &tid );    MTVERIFY(hThread);    // This thread has to wait for the new thread    // to init its globals and msg queue.    WaitForSingleObject(ghEvent, INFINITE);//等待事件有訊號    // The only place in the book we get to use    // the thread ID!//strdup 調用的是malloc所以需要free    char *szText = strdup("Thank you for buying this book.\n");    PostThreadMessage(tid, WM_JOB_PRINT_AS_IS, NULL, (LPARAM)szText);    szText = strdup("Text is easier to read forward.\n");    PostThreadMessage(tid, WM_JOB_PRINT_REVERSE, NULL, (LPARAM)szText);    szText = strdup("\nLOWER CASE IS FOR WHISPERING.\n");    PostThreadMessage(tid, WM_JOB_PRINT_LOWER, NULL, (LPARAM)szText);Sleep(4000);//給線程發訊息，退出PostThreadMessage(tid,WM_QUIT,0,0);    WaitForSingleObject(hThread, INFINITE);//等待線程退出，然後關閉控制代碼    CloseHandle(hThread);system("pause");    return 0;} VOID CALLBACK TimerFunc(    HWND hwnd,  // handle of window for timer messages     UINT uMsg,  // WM_TIMER message    UINT idEvent,   // timer identifier    DWORD dwTime )  // current system time{//取消編譯器的警告，沒有引用的變數    UNREFERENCED_PARAMETER(hwnd);    UNREFERENCED_PARAMETER(uMsg);printf("onTimer function\n");  //  PostThreadMessage(GetCurrentThreadId(), WM_QUIT,0,0);unsigned id = GetCurrentThreadId();PostThreadMessage(id, WM_LEIWEI,0,0);} /* * Call a function to do something that terminates * the thread with ExitThread instead of returning. */unsigned WINAPI ThreadFunc(LPVOID n){    UNREFERENCED_PARAMETER(n);    MSG msg;    // This creates the message queue.//建立一個訊息佇列    PeekMessage(&msg, NULL, 0, 0, PM_NOREMOVE);//設定事件有啟用    SetEvent(ghEvent);    // We'll run for two seconds    SetTimer(NULL, NULL, 500, (TIMERPROC)TimerFunc);    while (GetMessage(&msg, NULL, 0, 0))    {        char *psz = (char *)msg.lParam;        switch(msg.message)        {        case WM_JOB_PRINT_AS_IS:            printf("%s", psz);            free(psz);            break;        case WM_JOB_PRINT_REVERSE:            printf("%s", strrev(psz));            free(psz);            break;        case WM_JOB_PRINT_LOWER:            printf("%s", _strlwr(psz));            free(psz);            break;case WM_LEIWEI:printf("timer:............\n");break;        default:printf("message id=%0X\n",msg.message);            DispatchMessage(&msg);        }    }    return 0;}