C++进程间通信

# C++进程间通信 #

进程间通讯的四种方式：剪贴板、匿名管道、命名管道和邮槽

## 剪切板 ##

//设置剪切板内容

CString str;
this->GetDlgItemText(IDC_EDIT1, str);

OpenClipboard();//打开剪贴板查看,并防止其他应用程序修改剪贴板的内容.
EmptyClipboard();//EmptyClipboard Function该函数清空剪切板并释放剪切板内数据的句柄。函数在之后会将剪切板的所有权指派给当前打开剪切板的窗口。
HANDLE hclip = GlobalAlloc(GMEM_MOVEABLE, str.GetLength() + 1);
char *pBuf = (char *)GlobalLock(hclip);

//WideCharToMultiByte()//字形转换
strcpy(pBuf, str.GetBuffer());
//memcpy(pBuf, str.GetBuffer(), GetLength()+2);
GlobalLock(hclip);

SetClipboardData(CF_TEXT, hclip);//SetClipboardData是把指定数据按照指定格式放入剪切板中
CloseClipboard();//关闭剪贴板,这使其他窗口或程序能访问剪贴板。

//获得剪切板内容

OpenClipboard();
if (IsClipboardFormatAvailable(CF_TEXT))//是以NULL结尾的ASCII字符的文本格式,则该函数返回值为true,否则为false。
{
HANDLE hclip;
hclip = GetClipboardData(CF_TEXT);//用来打开剪贴板并获取剪贴板内容。
char *pBuf = (char *)GlobalLock(hclip);
GlobalUnlock(hclip);
CString STR;
SetDlgItemText(IDC_EDIT1, pBuf);
}
CloseClipboard();

//参考：
//http://bbs.kechuang.org/t/72605
//http://www.cnblogs.com/BoyXiao/archive/2010/12/25/1916677.html

## 匿名管道 ##

//父进程实现

//创建匿名管道
SECURITY_ATTRIBUTES sa;
sa.bInheritHandle = TRUE;
sa.lpSecurityDescriptor = NULL;
sa.nLength = sizeof(SECURITY_ATTRIBUTES);

if (!CreatePipe(&m_hRead, &m_hWrite, &sa, 0))
{
AfxMessageBox(_T("create pipe error"));
}

//子进程的创建
STARTUPINFO sui;
PROCESS_INFORMATION pi;
sui.cb = sizeof(STARTUPINFO);
ZeroMemory(&sui, sizeof(STARTUPINFO));

sui.dwFlags = STARTF_USESTDHANDLES;
sui.hStdInput = m_hRead;
sui.hStdOutput = m_hWrite;
sui.hStdError = GetStdHandle(STD_ERROR_HANDLE);

if (!CreateProcess(_T("../debug/child.exe"), NULL , NULL, NULL, TRUE, 0, NULL, NULL, &sui, &pi ))

{
AfxMessageBox(_T("创建子进程错误"));
}

//关闭进程 线程计数器
if (pi.hThread)
{
CloseHandle(pi.hThread);
}
if (pi.hProcess)
{
CloseHandle(pi.hProcess);
}

//发送数据

char buf[] = "this is pipe server";
DWORD dwWrite = 0;
if (!WriteFile(m_hWrite, buf, strlen(buf) + 1, &dwWrite, NULL))
{
AfxMessageBox(_T("write error parent"));
}

//接收数据

char buf[128] = {0};
DWORD dwRead = 0;
ReadFile(m_hRead, buf, sizeof(buf), &dwRead, NULL );

//子进程实现

//获取继承自父进程的匿名管道读写句柄
m_hRead = GetStdHandle(STD_INPUT_HANDLE);
m_hWrite = GetStdHandle(STD_OUTPUT_HANDLE);

//写入数据

char buf[] = "this is pipe child";
DWORD dwWrite = 0;
if (!WriteFile(m_hWrite, buf, strlen(buf) + 1, &dwWrite, NULL))
{
AfxMessageBox(_T("write error child"));
}

//读取数据

char buf[128] = {0};
DWORD dwRead = 0;
ReadFile(m_hRead, buf, sizeof(buf), &dwRead, NULL );

//参考
http://www.cnblogs.com/BoyXiao/archive/2011/01/01/1923828.html

## 命名管道 ##

//服务端

//创建命名管

m_hPipe = CreateNamedPipe(_T("\\\\.\\pipe\\mypipe"), PIPE_ACCESS_DUPLEX | FILE_FLAG_OVERLAPPED, /*OVERLAPPED是为了满足异步实现非阻塞的工能，当连接上用事件通知*/
0, 1, 1024, 1024, 0, NULL);

if (m_hPipe == INVALID_HANDLE_VALUE)
{
return;
}

//创建事件
HANDLE hEvent;
hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
if (!hEvent)
{
MessageBox(_T("创建事件对象失败！"));
CloseHandle(m_hPipe);
m_hPipe = NULL;
return;
}

OVERLAPPED ovlap;
ZeroMemory(&ovlap, sizeof(OVERLAPPED));
ovlap.hEvent = hEvent;

if (!ConnectNamedPipe(m_hPipe, &ovlap))
{
if (ERROR_IO_PENDING != GetLastError())
{
MessageBox(_T("等待客户连接失败！"));
CloseHandle(m_hPipe);
CloseHandle(hEvent);
m_hPipe = NULL;
return;
}
}

//重叠操作
if (WAIT_FAILED == WaitForSingleObject(hEvent, INFINITE))
{
MessageBox(_T("等待对象失败！"));
CloseHandle(m_hPipe);
CloseHandle(hEvent);
m_hPipe = NULL;
return;
}
CloseHandle(hEvent);

//写数据

char buf[] = "this is named pipe server";
DWORD dwWrite = 0;
WriteFile(m_hPipe, buf, strlen(buf) + 1, &dwWrite, NULL);

//读数据

char buf[128] = {0};
DWORD dwRead = 0;
ReadFile(m_hPipe, buf, 128, &dwRead, NULL);

//客户端

//连接命名管道
if (!WaitNamedPipe(_T("\\\\.\\pipe\\mypipe"), NMPWAIT_WAIT_FOREVER))
{
return;
}

m_hPipe = CreateFile(_T("\\\\.\\pipe\\mypipe"), GENERIC_READ | GENERIC_WRITE, FILE_SHARE_READ | FILE_SHARE_WRITE, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);

//写入数据

char buf[] = "this is named pipe client";
DWORD dwWrite = 0;
WriteFile(m_hPipe, buf, strlen(buf) + 1, &dwWrite, NULL);

//读取数据

char buf[128] = {0};
DWORD dwRead = 0;
ReadFile(m_hPipe, buf, 128, &dwRead, NULL);

//参考
//http://www.cnblogs.com/BoyXiao/archive/2011/01/02/1924188.html

## 邮槽 ##

//服务端

HANDLE hMail = CreateMailslot(_T("\\\\.\\mailslot\\myslot"), 424, MAILSLOT_WAIT_FOREVER, NULL);
if (hMail == INVALID_HANDLE_VALUE)
{
int nRes = GetLastError();
CString str;
str.Format(_T("%s"), nRes);
AfxMessageBox(str);
return;
}
char buf[424] = {0};
DWORD dwSize = 0;
ReadFile(hMail, buf, 424, &dwSize, NULL);
CString str;
str = buf;
MessageBox(str);

//客户端
HANDLE hMailslot;
hMailslot = CreateFile(_T("\\\\.\\mailslot\\myslot"), GENERIC_WRITE,
FILE_SHARE_READ, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
if (INVALID_HANDLE_VALUE == hMailslot)
{
MessageBox(_T("打开邮槽失败！"));
return;
}

char buf[] = "this is mail slot client";
DWORD dwSize = 0;
if (!WriteFile(hMailslot, buf, strlen(buf) + 1, &dwSize, NULL))
{
MessageBox(_T("写入邮槽失败！"));
}

//http://blog.csdn.net/kylin_p/article/details/5146797
//http://www.cnblogs.com/BoyXiao/archive/2010/12/31/1923462.html
//http://www.cnblogs.com/jzincnblogs/p/5192654.html