I'm trying to do some basic stuff in a C UDR. Following the docs,
mi_get_database_info takes a MI_CONNECTION* and a MI_DATABASE_INFO*.
However, the following causes Informix to give me "7520: Argument (2)
is NULL", which means a NULL was sent and Informix didn't expect it:

MI_CONNECTION *conn;
MI_DATABASE_INFO *dbInfo;
char* cpToEncrypt;
mi_lvarchar* cpOut;
fprintf(stderr,"encryptVarchar - entered");

cpOut = mi_var_copy(toEncrypt);
cpToEncrypt = mi_get_vardata(cpOut);

conn = mi_open(NULL, NULL, NULL);
/* If connection descriptor is NULL, there was an error *
connecting to the session context. */
if ( conn == NULL ) {
mi_db_error_raise(conn, MI_EXCEPTION, "func1: cannot
establish connection", NULL);
} else {
fprintf(stderr,"connected to db, getting dbInfo");
mi_get_database_info(conn,dbInfo);
fprintf(stderr,"User is %s", dbInfo->user_name);
mi_close(conn);
}

It fails on the mi_get_database_info(conn,dbinfo); line. FWIW, it
fails with the exact same message (argument 2 is null) even if I use
mi_get_default_database_info(dbInfo); which only has 1 parameter.

I can't find any examples of mi_get_database_info...what am I doing
wrong?

Thanks,

Bret

bret@welcometolazyhill.com wrote:
> I'm trying to do some basic stuff in a C UDR. Following the docs,
> mi_get_database_info takes a MI_CONNECTION* and a MI_DATABASE_INFO*.
> However, the following causes Informix to give me "7520: Argument (2)
> is NULL", which means a NULL was sent and Informix didn't expect it:
>
> MI_CONNECTION *conn;
> MI_DATABASE_INFO *dbInfo;
> char* cpToEncrypt;
> mi_lvarchar* cpOut;
> fprintf(stderr,"encryptVarchar - entered");
>
> cpOut = mi_var_copy(toEncrypt);
> cpToEncrypt = mi_get_vardata(cpOut);

You need to allocate the dbInfo struct.
>
> conn = mi_open(NULL, NULL, NULL);
> /* If connection descriptor is NULL, there was an error *
> connecting to the session context. */
> if ( conn == NULL ) {
> mi_db_error_raise(conn, MI_EXCEPTION, "func1: cannot
> establish connection", NULL);
> } else {
> fprintf(stderr,"connected to db, getting dbInfo");
> mi_get_database_info(conn,dbInfo);
> fprintf(stderr,"User is %s", dbInfo->user_name);
> mi_close(conn);
> }
>
> It fails on the mi_get_database_info(conn,dbinfo); line. FWIW, it
> fails with the exact same message (argument 2 is null) even if I use
> mi_get_default_database_info(dbInfo); which only has 1 parameter.
>
> I can't find any examples of mi_get_database_info...what am I doing
> wrong?
>
> Thanks,
>
> Bret
>