a deadlock retry mechanism is essentially down to checking for a deadlock having occurred in a transaction, and resubmitting that transaction if that's the case.

In Sybase::CTlib this means setting up a server message callback with some code that checks for error 1205 (deadlock), and re-sends the transaction that failed if that error code is detected.

For blk_xxx() calls this means that you'll need to "remember" the rows that you sent between blk_done() calls so that you can re-send those rows in case a deadlock is detected.

All of this can be written in perl and in your own code - no real need to subclass Sybase::CTlib (although you could do so) or delve into its C code.

Michael