To request JES to perform a SAPI operation on a client data set, you supply as SSS2CTKN the address of the CTOKEN for the data set you are interested in and set the selection flag SSS2SCTK. When you use the SSS2SCTK selection flag, you cannot use the SSS2SJBI selection flag, and vice versa.

When a data set is processed by a program written using SAPI, there is a distinction between a data set that is selected for processing and a data set that is selected for browsing. In the former case, the intention is to select the data set in much the same way as it would be selected for a writer (such as an external writer), which may or may not cause its state to be changed. In the latter case, the intention is to not change its state at all. The main purpose for this distinction is to prevent "noise" caused by unnecessary ENF signals.

You can set the flag SSS2SBRO when you know that the intention of a SAPI access is to browse a data set. When this flag is on, JES will not issue any signals for the SAPI access to this data set. When this flag is off JES will issue signals whenever a data set with a CTOKEN is selected or deselected by a SAPI Put/Get operation. Do not set this flag if you need to be informed of selects and deselects.

This flag controls signals for selects and deselects only. If a data set is purged by a SAPI Put operation (for example, by turning off flag SSS2DKPE), a signal will be issued even if SSS2SBRO is set.

You must use SAPI in order to suppress signals when accessing a data set for browse. When a Process Sysout (PSO) application selects or deselects a data set with a CTOKEN, a signal is always issued.

The SSS2SBRO flag is valid only for Put/Get requests.

Refer to SSI 79 in z/OS MVS Using the Subsystem Interface for a detailed description of SAPI.