Asynchronous output

Asynchronous output can easily be sent to an invalid destination by a simple typographical error.

This is because ETO provides IMS the flexibility to create user structures for any authorized user that is signed on. IMS automatically creates user structures for message switches and for the application insert call (ISRT) process when the LTERM cannot be found.

With ETO, all destinations are valid unless they are rejected by exit routines. Therefore, you can mistakenly create queues for users if you make typographical errors when entering any of the following:
  • Alternate PCBs
  • Message switches
  • /BROADCAST commands
  • MSC output

The LTERMs used in the previous situations are known as dead-letter queues. IMS provides commands for the MTO to monitor these queues and dispose of them.

The two types of asynchronous output destinations are valid and invalid.

A valid destination is one intended to receive output. An invalid destination is one that is not intended to receive output (for example, a misspelled destination).