Modify the idapi.cfg settings through code (2)

Problem/Question/Abstract:

How can my program access the idapi.cfg file and probably change its INIT (Local Share etc.) section?

Answer:

For 32bit only. You can of course use the registry to determine the default CFG File instead of passing it as a parameter here:

procedure ModifyCFG(const ACFGFile, AValue, AEntry, ACFGPath: string; SaveAsWin31:
  bool);
var
  hCfg: hDBICfg;
  pRecBuf, pTmpRec: pByte;
  pFields: pFLDDesc;
  Count: word;
  i: integer;
  Save: boolean;
  Reg: TRegistry;
const
  RegSaveWIN31: array[bool] of string = ('WIN32', 'WIN31');
begin
  hCfg := nil;
  pFields := nil;
  pRecBuf := nil;
  Save := False;
  Check(DbiOpenConfigFile(PChar(ACFGFile), False, hCfg));
  try
    Check(DbiCfgPosition(hCfg, PChar(ACfgPath))); {neccessary...?}
    Check(DbiCfgGetRecord(hCfg, PChar(ACfgPath), Count, nil, nil));
    pRecBuf := AllocMem(succ(Count) * 128); {128 additional safety...}
    pFields := AllocMem(Count * sizeof(FLDDesc));
    Check(DbiCfgGetRecord(hCfg, PChar(ACfgPath), Count, pFields, pRecBuf));
    for i := 1 to Count do
    begin
      if StrPas(pFields^.szName) = AEntry then
      begin
        pTmpRec := pRecBuf;
        Inc(pTmpRec, 128 * (i - 1));
        StrPCopy(PChar(pTmpRec), AValue);
      end;
      inc(pFields);
    end;
    dec(pFields, Count);
    Check(DbiCfgModifyRecord(hCfg, PChar(ACfgPath), Count, pFields, pRecBuf));
    Save := True;
  finally
    if hCfg <> nil then
      Check(DbiCloseConfigFile(hCfg, Save, True, SaveAsWin31));
    if pRecBuf <> nil then
      FreeMem(pRecBuf, succ(Count) * 128);
    if pFields <> nil then
      FreeMem(pFields, Count * sizeof(FLDDesc));
  end;
  {update registry SAVECONFIG value}
  Reg := TRegistry.Create;
  try
    Reg.RootKey := HKEY_LOCAL_MACHINE;
    if not Reg.OpenKey('SOFTWARE\Borland\Database Engine', False) then
      ShowMessage('Configuration Path not found')
    else
    begin
      Reg.LazyWrite := False;
      Reg.WriteString('SAVECONFIG', RegSaveWIN31[SaveAsWin31]);
      Reg.CloseKey;
    end;
  finally
    Reg.Free;
  end;
  {DbiExit/Init to re-read cfg... make absolutely sure there are no active
        DB components when doing this (it's is best done by a loader app)}
  Session.Close;
  Session.Open;
end;

ACFGPath would be '\SYSTEM\INIT\', AEntry would be 'LOCAL SHARE' und AValue would be 'TRUE' or 'FALSE'.