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Description of PICKPIPE

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PickPipe consists of three commands:

which is used to select which version of Pipelines is executed by the PIPE command.
which bootstraps the default CMS version of Pipelines explicitly: it NUCXLOADs DMSPIPE MODULE as EPIPMOD, and installs it with the name EPIPE. The nucleus extension then takes control. This is the same mechanism used by PIPE itself, although EPIPE MODULE is written in compiled REXX.
which bootstraps the uplevel or Field Test version of Pipelines explicitly. This is the same as EPIPE except that it NUCXLOADs PIPELINE MODULE as IPIPMOD and installs it with the name IPIPE.

The Field Test or Uplevel version of Pipelines has been integrated into z/VM 6.4. On CMS level 6.4 or later it is not necessary to load the Uplevel version of Pipelines before running modern plumbing. Therefore on 6.4 and later, the UPLEVEL argument is a synonym for the CMS argument and the field test level of Pipelines is not loaded.

PICKPIPE by default will use a version of Pipelines from a logical shared segment if possible. The shared segment names default to PIPES for the default CMS version, and PIPES+ for the uplevel version.

In essence, PICKPIPE does the following

  1. See if PIPMOD is NUCXLOADed.
  2. If it is, check the level of Pipelines with PIPE QUERY LEVEL (on newer levels, PIPE QUERY SOURCE), and whether it is loaded in a shared segment.
  3. If the level is wrong, or the shared segment is not as requested then SEGMENT PURGE the segment or NUCXDROP PIPMOD and re-check the level.
  4. If the level is wrong, or PIPMOD is not NUCXLOADed, try to SEGMENT LOAD Pipelines or failing that, to NUCXLOAD PIPELINE MODULE (uplevel version) or DMSPIPE MODULE (CMS) as PIPMOD.
  5. NUCXDROP PIPE and re-initialise it with PIPMOD INSTALL

More information is provided in PICKPIPE HELPCMS and PICKPIPE README.

Feedback: Bruce Hayden Washington Systems Center, IBM Advanced Technical Sales Support