windows shared memory sample - 2

win_shared_mem-2.cpp

#include <Windows.h>

#include <iostream>
#include <string>

using namespace std;

int main()
{
	string strMapName("ShareMemory");
	string strComData("This is common data");
	LPVOID pBuffer = nullptr;

	//打开一个命名为"ShareMemory"的内存映射文件对象
	HANDLE hMap = ::OpenFileMapping(FILE_MAP_ALL_ACCESS, 0, strMapName.c_str());

	if (NULL == hMap)
	{
		//打开失败，则创建该内存映射文件对象
		hMap = ::CreateFileMapping(INVALID_HANDLE_VALUE,
			NULL,
			PAGE_READWRITE,
			0,
			strComData.length() + 1,
			strMapName.c_str());
		if (hMap == nullptr)
		{
			cout << "CreateFileMapping failed." << endl;
			return 0;
		}

		//将该内存空间映射到进程的地址空间中
		pBuffer = ::MapViewOfFile(hMap, FILE_MAP_ALL_ACCESS, 0, 0, 0);
		if (pBuffer == nullptr)
		{
			cout << "MapViewOfFile failed." << endl;
			return 0;
		}
		////向内存中写入数据
		//strcpy_s((char*)pBuffer, strComData.length() + 1, strComData.c_str());
		//cout << "[WRITE] " << (char*)pBuffer << endl;
		//system("pause");
		while (1)
		{
			char s[100];
			cout << "plz input sth. to be transfered to A process." << endl;
			cin >> s;
			memcpy((PVOID)pBuffer, s, 100);
		}
	}
	else
	{
		//打开成功，直接将该内存空间映射到进程的地址空间中
		pBuffer = ::MapViewOfFile(hMap, FILE_MAP_ALL_ACCESS, 0, 0, 0);
		while (1)
		{
			cout << (char*)pBuffer << endl;
			cout << "A process: hit keyboard to receive from B process" << endl;
			if (getchar() == 'q')
				break;
		}
		//cout << "[READ]" << (char*)pBuffer << endl;
	}

	//解除内存空间映射
	if (pBuffer)
		::UnmapViewOfFile(pBuffer);

	//关闭内存映射文件对象句柄
	::CloseHandle(hMap);

	system("pause");
	return 0;
}