DWORD_PTR和unsigned __int3264，由COM / RPC编组__int3264作为64位值或32位值编组？ [英] Are DWORD_PTR and unsigned __int3264, signed __int3264 marshalled by COM/RPC as 64-bit values or 32-bit values?
问题描述
查看MIDL 64位移植指南，似乎指出应该在COM接口上使用DWORD_PTR类型传递指针值，以便以独立于平台的方式成功处理32位和64位平台。但是，一些实验似乎是
，表明如果在高4字节中有非0值，则由16位平台上的MIDL生成的代理/存根代码执行的编组不能成功编组64位值（即实际只发送低32位。）
Looking at the MIDL 64-bit porting guide, it seems to direct that pointer values should be passed using DWORD_PTR type on COM interfaces to successfully handle 32-bit and 64-bit platforms in a platform-independent way. However, some experimentation seems to indicate that the marshalling performed by MIDL-generated proxy/stub code on a 64-bit platform does not successfully marshal 64-bit values if they have non-0 values in the upper 4 bytes (i.e. only the lower 32-bits are actually transmitted).
例如，服务器想要返回[out] DWORD_PTR * pPointerValue：
* pPointerValue = 0x123456789ab ; $
在客户端，我看到值0x456789ab（高4字节的0x123丢失并替换为0）。
这是预期的吗？如果是这样，为什么MIDL移植指南表明DWORD_PTR对于在编组接口上传输8字节指针值有用呢？
For example, server would like to return [out] DWORD_PTR * pPointerValue:
*pPointerValue = 0x123456789ab;
On the client side, I see value 0x456789ab (the 0x123 in upper 4bytes is lost and replaced with 0).
Is this expected? If so, why does the MIDL porting guide indicate that DWORD_PTR should be useful for transmitting 8-byte pointer values across a marshalled interface?
是否有一些MIDL / IDL机制支持这一点特定于平台的方式（即32位平台上的32位和64位平台上的64位）？
Is there some MIDL/IDL mechanism to support this in a platform-specific way (i.e. 32 bits on 32-bit platform and 64 bits on 64-bit platform)?
如果我将无符号__in64 *指定为idl中的类型，则它会正确传输，但我希望有一个平台相关的数据类型，适用于两种类型的平台。
If I specify unsigned __in64 * as the type in idl, then it transmits correctly, but I would like to have a platform-dependent data type that works correctly for both types of platforms.
谢谢和问候，
Jon
推荐答案
感谢您在这里发帖。
>> DWORD_PTR和无符号__int3264，已签名__int3264由COM / RPC编组为64位值还是32位值？
DWORD_PTR是指针精度的无符号长类型，具有足够的位，以便指针可以转换为该类型并返回而不会丢失信息。它声明如下：
The DWORD_PTR is a unsigned long type for pointer precision with enough bits so that a pointer can be converted to that type and back without losing information. It's declared as below:
typedef ULONG_PTR DWORD_PTR;
#if defined(_WIN64)
typedef unsigned __int64 ULONG_PTR;
#else
typedef unsigned long ULONG_PTR;
#endif每种类型INT_PTR，UINT_PTR，LONG_PTR，ULONG_PTR和DWORD_PTR都是一个整数类型，与指针大小相同：32位32位位代码或64位代码中的64位。 .NET Framework中的相应类型是System.IntPtr或System.UIntPtr。
Each of the types INT_PTR, UINT_PTR, LONG_PTR, ULONG_PTR, and DWORD_PTR is an integer type with the same size as a pointer: 32 bits in 32-bit code or 64 bits in 64-bit code. The corresponding type in the .NET Framework is System.IntPtr or System.UIntPtr.
有关详细信息，请参阅下面的类似案例。
For more information, you could refer to this similar case below.
希望这可以帮助你。
最好的问候，
Baron Bi
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