Inside Macintosh: Open Transport /

Chapter 14 - AppleTalk Transaction Protocol (ATP) / ATP Reference

Options

There are several ATP-specific options, which are defined as the following:

#define ATP_OPT_REPLYCNT0x2110/* ATP Reply packet count */
#define ATP_OPT_DATALEN0x2111/* ATP packet data Length */
#define ATP_OPT_RELTIMER0x2112/* ATP release timer */
#define ATP_OPT_TRANID0x2113 /* Requests transaction ID */

The ATP_OPT_REPLYCNT option indicates the number of reply packets in the current ATP reply being received. The ATP_OPT_DATALEN option indicates a maximum data packet length that differs from the ATP default of 578; only the PAP server uses this option. The ATP_OPT_TRANID option adds the ATP transaction ID added to every request packet.

The ATP_OPT_RELTIMER option indicates the amount of time the responder must wait for a transaction release packet before it purges a request entry from its transactions list. Acceptable values are 0 (30 seconds), 1 (1 minute), 2 (2 minutes), 3 (4 minutes), 4 (8 minutes).

In order to use any option with ATP, you must indicate which protocol the option is intended for. To do this, you use a constant for the ATP protocol in the level field of the TOption structure when you specify an option.

#define ATK_ATP   'ATP '

ATP also allows you to use the generic Open Transport options OPT_RETRYCNT and OPT_INTERVAL, which are described in the chapter "Option Management" in this book.