type
 TDriveState(DS_NO_DISK, DS_UNFORMATTED_DISK, 
 DS_EMPTY_DISK, DS_DISK_WITH_FILES);

function DriveState(DrvLetter: Char): TDriveState;
var
 Mask: String[6];
 SearchRec: TSearchRec;
 oldMode: Cardinal;
 ReturnCode: Integer;
begin
 oldMode: = SetErrorMode(SEM_FAILCRITICALERRORS);
 Mask:= '?:\*.*';
 Mask[1] := DrvLetter;
 {$I-} ReturnCode := FindFirst(Mask, faAnyfile, SearchRec);
 FindClose(SearchRec);
 {$I+}
 case ReturnCode of
 0: Result := DS_DISK_WITH_FILES;
 -18: Result := DS_EMPTY_DISK;
 { DS_NO_DISK äëÿ DOS, ERROR_NOT_READY äëÿ WinNT, ERROR_PATH_NOT_FOUND äëÿ Win 3.1 }
 -21, -3: Result := DS_NO_DISK;
 else
 Result := DS_UNFORMATTED_DISK;
 end;
 SetErrorMode(oldMode);
end; { DriveState }

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