?
Solved

Using C DLLs

Posted on 1997-05-18
5
Medium Priority
?
155 Views
Last Modified: 2010-04-04
I now beleive thet the problem i described accured
because i made a 32bit DLL and tried to use it with DELPHI 1.0
which is 16 bit.

After making a 16 bit DLL, i keep getting , at run time, when
DELPHI is trying to LINK the DLL, a "can't find file" message.

The code looks like thet:

     .
     .
     .
  function CreateDiffJpeg (a : Integer):Integer;
  private
    { Private declarations }
  public
    { Public declarations }

  end;

var
  Form1: TForm1;

  index : integer;

implementation

{$R *.DFM}
function CreateDiffJpeg ;  external 'diffjpeg.dll' index 1;

procedure TForm1.Button1Click(Sender: TObject);
begin

     index := index +1;



end;

end.


Any idea ?
0
Comment
Question by:gur
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 3
5 Comments
 
LVL 1

Expert Comment

by:sleach
ID: 1336433
You should post the relevent code, so we can see what you might me doing wrong.

0
 

Accepted Solution

by:
GWalter earned 100 total points
ID: 1336434
In the Delphi Program link the dll-call like this:function ComInit (Handle: Integer): Integer; cdecl; extern "testdll.dll" index 12;
It is very import to supply the index, I couldnt manage to linka DLL with the Name. You can get the Index e.g. in B C++ 5.0by using IMPDEF. Now you can read the indexes in the .DEF file.! Indexes may change when recompiling the program.* cdecl =>  C-Stack-Handling

In the C++- DLL:
Declaration as folowing:
#ifdef __WIN32_DLL__
  #define exp __declspec(dllexport)
#else
  #define exp __declspec(dllimport)
#endif

int exp ComInit (int Handle);

(tried in MC C++ 4.0 , should also work with Borland C)

There might appear problems, when you link a DLL thats links another DLL, the DLL might be loaded twice.Gregor


0
 

Author Comment

by:gur
ID: 1336435
Edited text of question
0
 

Author Comment

by:gur
ID: 1336436
Edited text of question
0
 

Author Comment

by:gur
ID: 1336437
I am sorry, but the problem was in the C DLL :
It seems thet there must be two functions (except my regular code) : the WEP exit function (in 16 bit DLL) and an EntryPoint function.

0

Featured Post

On Demand Webinar: Networking for the Cloud Era

Did you know SD-WANs can improve network connectivity? Check out this webinar to learn how an SD-WAN simplified, one-click tool can help you migrate and manage data in the cloud.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

The uses clause is one of those things that just tends to grow and grow. Most of the time this is in the main form, as it's from this form that all others are called. If you have a big application (including many forms), the uses clause in the in…
Creating an auto free TStringList The TStringList is a basic and frequently used object in Delphi. On many occasions, you may want to create a temporary list, process some items in the list and be done with the list. In such cases, you have to…
If you’ve ever visited a web page and noticed a cool font that you really liked the look of, but couldn’t figure out which font it was so that you could use it for your own work, then this video is for you! In this Micro Tutorial, you'll learn yo…
This tutorial will teach you the special effect of super speed similar to the fictional character Wally West aka "The Flash" After Shake : http://www.videocopilot.net/presets/after_shake/ All lightning effects with instructions : http://www.mediaf…
Suggested Courses
Course of the Month13 days, 23 hours left to enroll

801 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question