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Message-ID: <002701c4d88f$3e12d100$0200a8c0@mindcooler>
From: =?iso-8859-1?Q?Mikael_=C5sberg?= <mikas493 AT student DOT liu DOT se>
To: <cygwin AT cygwin DOT com>
References: <000a01c4d883$eb5024f0$0200a8c0 AT mindcooler> <20041202153745 DOT GA29883 AT trixie DOT casa DOT cgf DOT cx> <001901c4d887$c873bfb0$0200a8c0 AT mindcooler>
Subject: Re: MSVC-dll under cygwin
Date: Thu, 2 Dec 2004 17:51:59 +0100
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>
>
>
>> On Thu, Dec 02, 2004 at 04:30:56PM +0100, Mikael ?sberg wrote:
>>>Hello, I was under the impression that using a Cygwin-compiled DLL
>>>under MSVC was extremely difficult, if not impossible, but using a
>>>MSVC-compiled DLL with programs compiled under Cygwin is possible?  I
>>>have test program that first calls LoadLibrary() and then for each
>>>function in the DLL it wants to call I call GetProcAddress().  However,
>>>when I try to call any function the program segfaults (the function
>>>pointers are not NULL).  The same test program works if compiled using
>>>MSVC.  Am I mistaken that this should work or is there an error
>>>somewhere?
>>
>> Since cygwin itself uses all sorts of non-cygwin dlls, it is a safe
>> assumption that it must be able to use non-cygwin dlls.
>>
>> However, if you are using stdio from msvcrt, you may run into problems.
>>
>> cgf
>>
>
> Thanks for the quick reply. I may have found the problem (will test
> later). In one of the functions, a parameter was declared to be const
> but it was declared as non-const in the definition. Seems like a mistake
> that can cause all sorts of weird problems.
>
> / Mikael
>
>

Okay, now I have tested the code and something is still not right. The DLL
contains functions for working with the Windows registry and my problem
is that if I call, for example, the function create_registry_key(), the 
string
parameter denoting the name of the key is garbled if called from a program
compiled under Cygwin.
The exact signature of that DLL-function is:
HKEY create_registry_key(const HKEY parent_key, const std::string& name);

This doesn't happen if I test the DLL with a

program compiled under MSVC. Any idea what might be wrong?



/ Mikael



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