A UDF that declares the result as a LOB_RESULT_LOCATOR type must use the FNC_LobAppend library function to append a sequence of bytes to the result.
The following code excerpt modifies the preceding code excerpt to show how to append data to a LOB_RESULT_LOCATOR result:
#define BUFFER_SIZE 500
void do_something ( LOB_LOCATOR *a,
LOB_RESULT_LOCATOR *result,
char sqlstate[6] )
{
BYTE buffer[BUFFER_SIZE];
FNC_LobLength_t actlen;
LOB_CONTEXT_ID id;
FNC_LobOpen(*a, &id, 0, BUFFER_SIZE);
FNC_LobRead(id, buffer, BUFFER_SIZE, &actlen);
FNC_LobAppend(*result, buffer, actlen, &actlen);
FNC_LobClose(id);
...
}