Creating Delphi 7 DLL callable by LibFunc

[adroege]

I am needing to create a custom DLL in Delphi7 that can be called from within Macro Scheduler using the LibFunc> method.

My first attempt causes LibFunc> to produce an access violation and lock up Macro Scheduler.


Can someone who as done this post the Delphi source code for a very simple example to get me started on the right track?

Marcus?


Thanks.

[Marcus Tettmar]

Make sure it is StdCall.

DLLs do not fail gracefully. Any slight error in the way you call it can lead to nasty errors.

Make sure it's stdcall, stick to simple integers and character pointers (NOT strings - use pchar).

Here's a simple Delphi DLL:

Code: Select all

library simple_dll;

uses
  SysUtils, dialogs,
  Classes;

{$R *.res}

Function MyFunction(somestring: pansichar; anumber: integer; outputbuffer: pansichar): integer; stdcall;
begin
  ShowMessage(somestring);
  StrPCopy(outputbuffer,'boo');
  result := anumber * 5;
end;

exports MyFunction name 'MyFunction';

end.

And here's the MacroScript code to use it:

Code: Select all

Let>dll=C:\...\simple_dll.dll
Let>buffer_SIZE=255
LibFunc>dll,MyFunction,res,Hello World,4,buffer

This demonstrates passing a string to the DLL, passing an integer, getting back an integer result and also passing back a string via an output buffer.

Hope this helps.