Sending Backout on Sync Point Conversations

To send a Backout, an FMH-7 containing a sense code of 0x08240000 or 0x08240001 is sent on the session. This is done using the SEND_ERROR or MC_SEND_ERROR verb. To allow SNA Server to send the appropriate sense data, the SEND_ERROR and MC_SEND_ERROR verbs are modified as follows:

• A new field, err_type, is added to allow the TP to specify the type of error. The default is AP_PROG (0x00), which means existing TPs will continue to work unmodified.
• The err_type field in both verbs can take one of two new values, specifying the sense codes to be generated by SNA Server:

  AP_BACKOUT_NO_RESYNC for sense code 0x08240000

  AP_BACKOUT_RESYNC for sense code 0x08240001