如何做Windows处理继承

Question

我有父进程和子进程,在父进程中我声明句柄将被继承,如http://msdn.microsoft.com/en-us/library/windows/desktop/ms724466%28v=vs.85 %29.aspx:

...
SECURITY_ATTRIBUTES sa;
sa.nLength = sizeof(SECURITY_ATTRIBUTES); 
sa.bInheritHandle = TRUE; 
sa.lpSecurityDescriptor = NULL;
// Create a pipe for the Parent process's STDOUT.  
if ( ! CreatePipe(&hChildReadPipe, &hParentWritePipe, &sa, 0) )
{
    _tprintf(_T("Error creating Pipe\n")); 
}
...

// Start the child process. 
if( !CreateProcess(
        _T("..\\Debug\\Child.exe"),
        _T("hChildReadPipe"),   // Command line.
        NULL,                   // Process handle not inheritable.
        NULL,                   // Thread handle not inheritable.
        TRUE,                   // Set handle inheritance to TRUE.
        CREATE_NEW_CONSOLE,     // No creation flags.
        NULL,                   // Use parent's environment block.
        NULL,                   // Use parent's starting directory.
        &si,                    // Pointer to STARTUPINFO structure.
        &pi )                   // Pointer to PROCESS_INFORMATION structure.
    )
    {
        printf( "\nCreateProcess failed (%d).\n", GetLastError() );
    return FALSE;
    }

我的问题是如何获取命令行传递给子进程的hChildReadPipe句柄,在MSDN中他们建议使用GetCommandLine(),但这只返回命令行字符串,如何将此字符串转换为可用的HANDLE？

我试过CreateFile()但它不起作用......

谢谢

Answer 1

我的第一个建议是阅读使用重定向输入和输出创建子进程.

但是,如果您的要求是不要触摸stdin或stdout(或其他相关的HANDLE),那么您可以将句柄转换为整数值(UINT_PTR value = (UINT_PTR)hChildReadPipe;)并将其作为字符串(__ultoa())传递给命令行.然后,子进程需要读取命令行(UINT_PTR value = strtoul())的整数值并将其强制转换回HANDLE(HANDLE hChildReadPipe = (HANDLE)value;).

要记住的重要事情是从微软处理继承摘录,"An inherited handle ... has the same value ...".