Using an uninitialized structure
Regan Heath
regan at netmail.co.nz
Mon Sep 3 09:41:02 PDT 2007
B. Schulte wrote:
> Regan Heath Wrote:
>
>> B. Schulte wrote:
>>> Regan Heath Wrote:
>>>
>>>> Where is the definition of the CHAR_INFO structure? Have you defined it
>>>> in your code? eg.
>>>>
>>>> import std.c.windows.windows;
>>>>
>>>> extern(C)
>>>> {
>>>> struct CHAR_INFO {
>>>> union _Char {
>>>> WCHAR UnicodeChar;
>>>> CHAR AsciiChar;
>>>> }
>>>> _Char Char;
>>>> WORD Attributes;
>>>> }
>>>> alias CHAR_INFO* PCHAR_INFO;
>>>> }
>>>>
>>>> void main()
>>>> {
>>>> CHAR_INFO buffer[];
>>>> buffer.length = 100;
>>>> foreach( inout CHAR_INFO ci; buffer ) { ci.Char.AsciiChar = ' ';
>>>> ci.Attributes=7; }
>>>> }
>>>>
>>>> Regan
>>> Well, the CHAR_INFO structure is stored in the win32.wincon file. There was something I took from dsource to use the winAPI methods.
>>>
>>> I didn't want to write in orginal files to fix a problem. I thought about fixing the problem somewhere else. (Don't modify the wincon.d)
>>>
>>> However, it still doesn't work.
>>> Error 42: Symbol Undefined _D5win326wincon9CHAR_INFO6__initZ
>>>
>>>
>>> There must be some way to use uninitialized variables :(
>> There is, but I don't believe it has anything to do with the error
>> you're getting. :)
>>
>> You are missing a symbol, the symbol you are missing is mangled in such
>> a way that it is clear that it is a D symbol, which means you have
>> defined CHAR_INFO as a D struct, instead of using extern (C) as I have
>> shown you above.
>>
>> What dsource project is win32.wincon in? Perhaps CHAR_INFO isn't
>> declared as extern (C) in there...
>>
>> FYI, you can allocate an array of CHAR_INFO structures without
>> initialising like this:
>>
>> CHAR_INFO[500] abuffer = void;
>>
>> this is a fixed length array however, perhaps not what you want?
>>
>>
>> Regan
>
> Well, it really wasn't declared as extern(C). But I inserted it and declared it as extern(C). Don't know why, but it still don't work.
>
> Here is the dsource project:
> http://dsource.org/projects/core32
I can't see the win32.wincon file in the svn for that project:
http://dsource.org/projects/core32/browser/trunk/core32/win32
I retract my comment about extern (C) I think maybe this has something
to do with how you're compiling it, the command line you're using.
Regan
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