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Visual Studio85
Hi

Is there any chance anyone could tell me how to go from an HRESULT to text?

I am using ADO via COM, and am getting the following HRESULT when I try to

call _Connection_Open:



-2147467259



I am calling it with

#define TESTCONNECT _T("Provider=SQLOLEDB;Integrated Security=SSPI;Data

Source=(local)")

...

hr = _Connection_Open(cndb, TESTCONNECT, _T(""), _T(""), -1);



I would like to know how to fix this error which even already I am

suspecting to be due to the fact that TESTCONNECT is not BSTR, however, I

would like to know how to get from that HRESULT to a meaningful message, when

calling functions of the ADO library.

I am using the SDK not visual studio/ATL/MFC, so _com_issue_error and

anything else in <comutil.h>is out.


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"Bonj" <Bonj@discussions.microsoft.com>wrote in message

For system-defined HRESULTs, use

FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM). If you want to see it while

debugging, put a variable into the Watch window and type ",hr" (without

quotes) after the variable name. There's also Error Lookup tool under

Tools menu in the IDE.



That would be 0x80004005 E_FAIL "Unspecified error".

--

With best wishes,

Igor Tandetnik



With sufficient thrust, pigs fly just fine. However, this is not

necessarily a good idea. It is hard to be sure where they are going to

land, and it could be dangerous sitting under them as they fly

overhead. -- RFC 1925





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Igor Tandetnik wrote:

Helpful, eh? :-) No, I don't mean your reply, I mean MS'

error codes.

-

OK

I see FormatMessage defined in the docs as

DWORD FormatMessage(

DWORD dwFlags,

LPCVOID lpSource,

DWORD dwMessageId,

DWORD dwLanguageId,

LPTSTR lpBuffer,

DWORD nSize,

va_list* Arguments

);

So I presumably pass FORMAT_MESSAGE_FROM SYSTEM as the first parameter, ...

and the address of my HRESULT as the second?



I can guess what lpBuffer and nSize are for...

What about dwMessageID, dwLanguageID and va_list?

Can I just pass NULL to these?







"Igor Tandetnik" wrote:

I know, good aren't they! :-)

My favourite is "Unknown catastrophic failure".

Or is it just "Catastrophic failure"?



(as if that would be a known unknown..)

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"Bonj" <Bonj@discussions.microsoft.com>wrote in message

Why don't you go just one step further and actually read the complete

docs page? Which part of this do you have difficulty understanding:



If neither of these flags is set in dwFlags, then lpSource is ignored.

dwMessageId - Message identifier for the requested message.



Why do you feel the need to guess? Presumably, you are literate, so why

can't you just read the documentation in lieu of guesswork?

--

With best wishes,

Igor Tandetnik



With sufficient thrust, pigs fly just fine. However, this is not

necessarily a good idea. It is hard to be sure where they are going to

land, and it could be dangerous sitting under them as they fly

overhead. -- RFC 1925





-

Well, I didn't want to get bogged down in things that were irrelevant, such

as language id.



Right, OK - so dwMessageID is the HRESULT...the only difficulty I had in

unerstanding that was that an HRESULT could be represented by an LPCVOID

*or* a DWORD, if one of the parameters was of type HRESULT, I would have

understood it instantly. Likewise, I would have got it if it had said "this

parameter can take a message code, such as an HRESULT". Sorry if I was a bit

slow.





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Bonj wrote:

So, as you didn't want to get "booged down", you asked this newsgroup to do

all the "bogging down" for you, right?



Arnaud

MVP - VC





-

Well, no - I wouldn't wish "getting bogged down in language ids" on

anybody - it was just really that I didn't understand why the function

didn't take an HRESULT as one of its parameters - I thought that other

people who use it on a day-to-day basis would have already sifted out that

and be able to reply in seconds.

Sorry.



"Arnaud Debaene" <adebaene@club-internet.fr>wrote in message



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