DuplicateHandle 伪句柄 与 实句柄的应用

如果把GetCurrentThread()返回值传递给一个HANDLE句柄，用它进行ResumeThread,结果肯定不是我们想要的。下面的例子详细描述了伪句柄的调用结果：

#include "stdafx.h"
#include <stdio.h>
#include <iostream>
#include <windows.h>
#include <process.h>
using namespace std;
#pragma warning(disable:4996)
HANDLE hThread = NULL;
unsigned int __stdcall ProcessInfo(void* lp)
{
	string str = *(string*)lp;
	delete lp;
	hThread = GetCurrentThread();
	while(true){
		SuspendThread(GetCurrentThread());
		cout<<str.c_str()<<endl;
	}
	_endthreadex(0);
	return 0;
}
int _tmain()
{
	string *pStr = new string;
	*pStr = "老婆, I Love You";
	unsigned int dwThreadID;
	SECURITY_ATTRIBUTES sa;
	sa.bInheritHandle = FALSE;
	sa.lpSecurityDescriptor = NULL;
	sa.nLength = sizeof(SECURITY_ATTRIBUTES);
	HANDLE hCom = (HANDLE)_beginthreadex(&sa, 0, ProcessInfo, (void*)pStr, 0, &dwThreadID);
	Sleep(1000);//线程肯定会先执行到SuspendThread，主线程一直在延时，并且全局hThread得到线程的伪句柄
	ResumeThread(hThread);
	printf("hThread的句柄值是： %d\n", hThread);
	Sleep(INFINITE);
	CloseHandle(hCom);
	return 0;
}

结果显示,hThread是-2，线程没有输出任何东西

修改代码如下：

#include "stdafx.h"
#include <stdio.h>
#include <iostream>
#include <windows.h>
#include <process.h>
using namespace std;
#pragma warning(disable:4996)
HANDLE hThread = NULL;
unsigned int __stdcall ProcessInfo(void* lp)
{
	string str = *(string*)lp;
	delete lp;
	DuplicateHandle(GetCurrentProcess(), GetCurrentThread(), GetCurrentProcess(),
		&hThread, 0, 0, DUPLICATE_SAME_ACCESS);
	while(true){
		SuspendThread(GetCurrentThread());
		cout<<str.c_str()<<endl;
	}
	_endthreadex(0);
	return 0; 

}
int _tmain()
{
	string *pStr = new string;
	*pStr = "老婆, I Love You";
	unsigned int dwThreadID;
	SECURITY_ATTRIBUTES sa;
	sa.bInheritHandle = FALSE;
	sa.lpSecurityDescriptor = NULL;
	sa.nLength = sizeof(SECURITY_ATTRIBUTES);
	HANDLE hCom = (HANDLE)_beginthreadex(&sa, 0, ProcessInfo, (void*)pStr, 0,
		&dwThreadID);
	Sleep(1000);//线程肯定会先执行到SuspendThread，主线程一直在延时，并且全局hThread得到线程的伪句柄
		ResumeThread(hThread);
	printf("hThread的句柄值是： %d\n", hThread);
	Sleep(INFINITE);
	CloseHandle(hCom);
	return 0;
}

运行正常

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