IBM Tivoli NetView for z/OS Programming: Pipes - IBM notice

Chapter 3. NetView Pipelines Device Drivers
This chapter documents general-use programming interface and associated
guidance information. For information about using pipelines in high-level
languages, see IBM Tivoli NetView for z/OS Programming: PL/I and C.
Device drivers are stages that move data between your pipeline and other system
resources (such as command procedure variables, DASD, keyboards, displays, and
so on).
When using drivers that can be placed anywhere in a pipeline (such as, STEM,
VAR, and SAFE) be aware that they work differently depending on where they are
placed. When first in a pipeline, these device drivers read from the system
resource. When used anywhere else in the pipeline, they write to the system
resource, often replacing existing data.
Attention: You can overwrite or destroy data when you misplace these device
drivers.
Interfacing with the Task: CONSOLE, HELDMSG, LITERAL, LOGTO
This section describes several device drivers that interface with the task. You can:
v Display pipeline contents on the screen (CONSOLE)
v Route pipeline contents to another pipeline (CONSOLE)
v Copy held messages from your operator console (HELDMSG)
v Insert text into the pipeline (LITERAL)
v Copy pipeline contents to a specified log (LOGTO)
Displaying Messages: CONSOLE
The CONSOLE stage enables the user to:
v Display messages on the screen while these messages remain in the pipeline for
use by the next stage.
v Remove the status of held messages that are in the pipeline before rewriting
them on the screen (using the DELETE option).
v Return messages to its caller (without displaying the messages), when it is a
stage of the inner pipeline as part of a PIPE-within-a-PIPE structure.
Example 1: Displaying Results While Avoiding Logging
This example shows how to use the CONSOLE stage with the ONLY option to
display messages in the pipeline without logging or exposing the messages:
PIPE NETVIEW LIST ’’ | CONSOLE ONLY
Output from the pipeline follows:
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