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Runtime dynamic linking using .dli files
In Ultimate++ you can use .dli file to automatize generating .dll wrapper objects. To create such object you have to provide ".dli" file with content like (actual example is for Lotus Notes client .dll):
FN(WORD, OSLoadString, (HMODULE hModule, STATUS StringCode, char *retBuffer, WORD BufferLength))
FN(WORD, OSTranslate, (WORD TranslateMode, char far *In, WORD InLength, char far *Out, WORD OutLength))
FN(STATUS, NotesInitExtended, (int argc, char **argv))
FN(STATUS, OSPathNetConstruct, (char *PortName, char *ServerName, char far *FileName, char *retPathName))
FN(STATUS, NSFDbOpen, (char far *PathName, DBHANDLE far *rethDB))
FN(STATUS, NSFDbClose, (DBHANDLE hDB))
...........
- basically, this is somewhat "reparsed" header file for .dll. Then place
#define DLLFILENAME "nnotes.dll"
#define DLIMODULE NOTES
#define DLIHEADER <notes/notes.dli>
#define DLLCALL LNPUBLIC
#include <Core/dli_header.h>
to common header file and
#define DLLFILENAME "nnotes.dll"
#define DLIMODULE NOTES
#define DLIHEADER <notes/notes.dli>
#define DLLCALL LNPUBLIC
#include <Core/dli_header.h>
to some .cpp file or, if you need that .dll just in single .cpp file, you can use
#define DLLFILENAME "nnotes.dll"
#define DLIMODULE NOTES
#define DLIHEADER <notes/notes.dli>
#define DLLCALL LNPUBLIC
#include <Core/dli.h>
in .cpp (this is equivalent of placing both above variants to .cpp).
This creates global function NOTES() returning the object instance that has all .dll functions described in .dli file defined as its methods. Moreover, it has operator bool that can be used to test whether .dll is present:
char h[256];
if(NOTES())
NOTES().OSLoadString(GetModuleHandle(NULL), ERR(nError), h, 255);
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