On Aug 27, 2007, at 11:28 AM, Dave Jones wrote:
Hello, Adam.
Yup this would be a very slick way of distributing software; but I
don't think the format of the data on the DVDs is documented
anywhere, nor to I think IBM will be documenting how to use the
FTPGET stage, either. During the recent 5.3 ESP program, I asked
about getting FTPGET documented, but never heard back anything
official from IBM.
Plus, you will notice that there are *two* undocumented stages used
by the DVD restore process: FTPGET itself, and the stage right
behind it: ECKDREST...that's not a part of the normal pipeline
stage collection, either.
Yeah, but I don't need to know *how* either of those stages work,
really.
I did some experimenting; ECKDREST works if you just download (er,
and PIPE UNPACK) the disk files. FTPGET appears to just pull the
binary image of the files (hunh....come to think of it, if I were
doing a whole mod-3, I might need some ridiculous amount of memory to
buffer the output of the initial FTPGET stage anyway, although if it
does it one record at a time, not so much). UNPACK, well, UNPACKs to
some track image format that ECKDREST consumes that I don't actually
need to care about.
Yes, of course this might break at some point if IBM changes their
formats, but it works with z/VM 5.1 through 5.3, which is, frankly,
almost everyone I currently care about supporting for this product.
I see that Alan just confirmed that: if they change without notice,
they will do so on a release boundary, and it will be obvious because
the "requires z/VM 5.1 or later" for Level 2 installation will change
to...something else.\
But since it's not documented, I guess I *do* need to figure out what
the format that ECKDREST uses is, so I can dump to it, run it through
PIPE PACK and then split to 4M chunks or whatever it is that the CKD
files actually are. ("COPYFILE ( FROM x FOR y PACK" would do this
split, right?)
Adam
