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* macro - 4 messages, 4 authors
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* smart pointer with custom deconstruction? - 2 messages, 2 authors
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* networking libraries - 4 messages, 3 authors
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* Pass by pointer - segmentation fault - 2 messages, 1 author
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* ALGORITHM - 1 messages, 1 author
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* Singletons / classes with only one member - 4 messages, 3 authors
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* Accessing & Updating an STL list - 1 messages, 1 author
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* std::sort causes segfault when sorting class arrays - 1 messages, 1 author
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==============================================================================
TOPIC: macro
http://groups.google.com/group/comp.lang.c++/t/84731ce3c14b7152?hl=en
==============================================================================
== 1 of 4 ==
Date: Fri, Feb 27 2009 11:47 pm
From: "Fernando A. Gómez F."
Sam wrote:
> asmcad writes:
>
>> i'm using wxWidget and i saw same strange macro:
>>
>> # define WXDLLIMPEXP_CL
>>
>> class WXDLLIMPEXP_CL classname {
>> ....
>> ..
>>
>> why they do this? what does it mean? does anybody write code like
>> this?
>
> Some technically flawed operating systems may require usage of some
> non-standard keywords in order to define certain attributes of classes
> that must be specified in order to get the wanted results.
>
> Your library's configuration script will install the appropriate
> definition of this macro, when your library is installed on that
> particular operating system.
>
In Visual C++, you usually do something like this:
#ifdef MYDLL_EXPORTS
#define MYDLL_API __declspec(dllexport)
#else
#define MYDLL_API __declspec(dllimport)
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