I'm reading the documentation and it's telling me this; In some cases, this service may not return a device UCB, but instead may return a zero UCB address or the address of a dummy UCB. This may occur for DDs that represent DD DUMMY requests, VIO data sets, SYSOUT data sets, in-stream data sets, and some SMS-managed data sets. A dummy UCB can be identified using the UCBDUMMY field in the UCB. A dummy UCB may not have all of the UCB segments that a device UCB may have and not all services that are used for processing device UCBs may support dummy UCBs.
I don't see a UCBDUMMY field in mapping macro IEFUCBOB. Mark Jacobs Sent from [ProtonMail](https://protonmail.com), Swiss-based encrypted email. GPG Public Key - https://api.protonmail.ch/pks/lookup?op=get&[email protected] ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
