Hi everybody,

since a few days I try to get a UDF up and running on my computer. I tried
to write it in Delphi.
The sample Modulo UDF is working fine on my computer. But now I need a UDF
returning a simple calculation. Each time I call the external function in a
select, the server crashes.
Can anybody tell me what I'm doing wrong? I tried as data types in the
declare external function syntax "float" and "double precision"

DECLARE EXTERNAL FUNCTION DISTANCE
DOUBLE PRECISION, DOUBLE PRECISION, DOUBLE PRECISION, DOUBLE PRECISION
RETURNS DOUBLE PRECISION
ENTRY_POINT 'Distance' MODULE_NAME 'DistanceUDF';

And my unit in the DLL-project looks as follows:

unit Unit1;

interface

function Distance(var lon1, lon2, lat1, lat2: real): real; cdecl; export;

implementation
uses MATH;

function Distance(var lon1, lon2, lat1, lat2: real): real;
begin
result := 6740 * arccos(( SIN(lat1/57.29577951) * SIN(lat2/57.29577951) )
+ (COS(lat1/57.29577951) * COS(lat2/57.29577951) *
COS((lon1/57.29577951)-(lon2/57.29577951))) );
end;

end.


Does anyone have an idea what the problem could be?

Thanks in advance
Oliver



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