用C ++在Windows中打开命名管道的ATL方法是什么？

Question

hPipe = CreateFile( 
         lpszPipename,   // pipe name 
         GENERIC_READ |  // read and write access 
         GENERIC_WRITE, 
         0,              // no sharing 
         NULL,           // default security attributes
         OPEN_EXISTING,  // opens existing pipe 
         0,              // default attributes 
         NULL);          // no template file 

How to convert the above to ATL way so that the pipe is automatically closed when the COM component is destroyed?

Answer 1

I have to guess what COM component you are referring to, since your post was vague. But I'm guessing you have written a COM component that wraps or otherwise uses a named pipe, and you want it to be automatically released (ala RAII ) when this COM component is destroyed.

In this case, you would put any cleanup code in the component's FinalRelease() method, for example:

void CoMyObject::FinalRelease()
{
  CloseHandle(my_pipe_handle_);
}

The other side of the one-time-cleanup coin is one-time-initialization code. If you also want to open this named pipe when the COM component is instantiated -- which your title suggests but your post doesn't say -- then you would do this in your object's FinalConstruct() method:

HRESULT CoMyObject::FinalConstruct()
{
  my_pipe_handle_ = CreateFile( 
         lpszPipename,   // pipe name 
         GENERIC_READ |  // read and write access 
         GENERIC_WRITE, 
         0,              // no sharing 
         NULL,           // default security attributes
         OPEN_EXISTING,  // opens existing pipe 
         0,              // default attributes 
         NULL);          // no template file }

  return S_OK;
}

Answer 2

#include <atlbase.h>
#include <atlfile.h>

CAtlFile m_file;
m_file.Create(lpszPipeName, GENERIC_READ|GENERIC_WRITE, 0, OPEN_EXISTING);

Presumably, m_file is a member variable of your class. When your class instance gets its final release (and subsequently destroyed), the destructor of m_file will close the handle associated with the pipe.