Transaction Handle Declaration Requirements
A transaction handle must be declared and initialized to zero before use. The following code illustrates how to declare and initialize a transaction handle:
#include <ibase.h> . . . /* Declare a transaction handle. */ isc_tr_handle tr1; . . . /* Initialize the handle. */ tr1 = 0L;
For more information about declaring, initializing, and using transaction handles, see Working with Transactions.