Date: Wed, 9 Feb 2005 20:02:05 -0700 (MST)
From: Seamus Thomas Carroll <carrolls@cpsc.ucalgary.ca>
To: pgsql-interfaces@postgresql.org
Subject: Help with adding C-Language Functions
Message-ID: <Pine.LNX.4.60.0502091954340.5503@frost>
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed

Hi,

I am trying to add a C-Language Function.  I have created a small example 
in file BlackboardFunctions.c.

#include <postgres.h>
#include <fmgr.h>

PG_FUNCTION_INFO_V1(add_one);

Datum
add_one(PG_FUNCTION_ARGS)
{
     int32   arg = PG_GETARG_INT32(0);

     PG_RETURN_INT32(arg + 1);
}

The make file:
make:
         cc -fpic -c BlackboardFunctions.c -I /home/grads/carrolls/source/postgresql-7.4.5/src/include/
         cc -shared -o BlackboardFunctions.so BlackboardFunctions.o

Everything compiles nicely and when i try to add the function using:
Blackboard=# CREATE FUNCTION add_one(integer) RETURNS integer
Blackboard-#      AS '/home/grads/carrolls/gradstudies/implementation/BlackboardFunctions/BlackboardFunctions', 'add_one'
Blackboard-#      LANGUAGE C STRICT;

I get the following error:
ERROR:  could not find function "add_one" in file 
"/home/grads/carrolls/gradstudies/implementation/BlackboardFunctions/BlackboardFunctions.so"

A grep of BlackboardFunction.so finds add_one.
I figure i must be doing something obviously wrong but for the life of me 
i cant figure out what that might bt.  Can anyone recommend a course 
of action?

Thank you,

Seamus