Обсуждение: problem with calling c functions

I'll just show an example:

I have:

int myfunc (text *a, text* b)
{
 return(12);
}

in psql:

test=# CREATE FUNCTION myfunc(text, text)
test-# RETURNS integer
test-# AS
'/home/hchapman/src/nms/wwp_database/c-functions/call_dynamic.so'
test-# LANGUAGE 'C';
CREATE
test=# SELECT myfunc('aa','ss') as result;
 result
--------
     12
(1 row)

test=# SELECT myfunc('aa',NULL) as result;
 result
--------

(1 row)

test=#

oops, got a little trigger-happy with the send button.

Question: Why isn't 12 printed after the second SELECT statement?

Thanks,

R.

On Thu, 21 Sep 2000, Richard Harvey Chapman wrote:

> I'll just show an example:
>
> I have:
>
> int myfunc (text *a, text* b)
> {
>  return(12);
> }
>
> in psql:
>
> test=# CREATE FUNCTION myfunc(text, text)
> test-# RETURNS integer
> test-# AS
> '/home/hchapman/src/nms/wwp_database/c-functions/call_dynamic.so'
> test-# LANGUAGE 'C';
> CREATE
> test=# SELECT myfunc('aa','ss') as result;
>  result
> --------
>      12
> (1 row)
>
> test=# SELECT myfunc('aa',NULL) as result;
>  result
> --------
>
> (1 row)
>
> test=#
>

Richard Harvey Chapman <hchapman@3gfp.com> writes:
> Question: Why isn't 12 printed after the second SELECT statement?

NULL arguments/results for user functions are a longstanding problem
(check the list archives).  This is finally fixed in current sources
for 7.1, but there's no good workaround in existing releases.

            regards, tom lane